**Lecture 1** Play Video |
**Introduction to physics | One-dimensional motion** An overview video of what physics is about as we delve deeper in future videos! Watch the next lesson: https://www.khanacademy.org/science/physics/one-dimensional-... |

**Lecture 2** Play Video |
**Intro to vectors & scalars | One-dimensional motion** Distance, displacement, speed and velocity. Difference between vectors and scalars. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/one-dimensional-... Missed the previous lesson? https://www.khanacademy.org/science/physics/one-dimensional-... |

**Lecture 3** Play Video |
**Calculating average velocity or speed | One-dimensional motion** Example of calculating speed and velocity. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/one-dimensional-... Missed the previous lesson? https://www.khanacademy.org/science/physics/one-dimensional-... |

**Lecture 4** Play Video |
**Solving for time | One-dimensional motion** Simple example of solving for time given distance and rate. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/one-dimensional-... Missed the previous lesson? https://www.khanacademy.org/science/physics/one-dimensional-... |

**Lecture 5** Play Video |
**Displacement from time and velocity example | One-dimensional motion** Worked example of calculating displacement from time and velocity. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/one-dimensional-... Missed the previous lesson? https://www.khanacademy.org/science/physics/one-dimensional-... |

**Lecture 6** Play Video |
**Acceleration | One-dimensional motion** Calculating the acceleration of a Porsche. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/one-dimensional-... Missed the previous lesson? https://www.khanacademy.org/science/physics/one-dimensional-... |

**Lecture 7** Play Video |
**More on Newton's first law of motion** Newton's First Law (Galileo's Law of Inertia). Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/forces-newtons-l... Missed the previous lesson? https://www.khanacademy.org/science/physics/forces-newtons-l... |

**Lecture 8** Play Video |
**Newton's second law of motion | Forces and Newton's laws of motion** Newton's Second Law of Motion: F=ma. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/forces-newtons-l... Missed the previous lesson? https://www.khanacademy.org/science/physics/forces-newtons-l... |

**Lecture 9** Play Video |
**Newton's third law of motion | Forces and Newton's laws of motion** Every action has an equal and opposite reaction. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/forces-newtons-l... Missed the previous lesson? https://www.khanacademy.org/science/physics/forces-newtons-l... |

**Lecture 10** Play Video |
**Airbus A380 take-off time | One-dimensional motion** Figuring how long it takes an a380 to take off given a constant acceleration. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/one-dimensional-... Missed the previous lesson? https://www.khanacademy.org/science/physics/one-dimensional-... |

**Lecture 11** Play Video |
**Airbus A380 take-off distance | One-dimensional motion** How long of a runway does an A380 need? Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/one-dimensional-... Missed the previous lesson? https://www.khanacademy.org/science/physics/one-dimensional-... |

**Lecture 12** Play Video |
**Why distance is area under velocity-time line** How long of a runway does an A380 need? Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/one-dimensional-... Missed the previous lesson? https://www.khanacademy.org/science/physics/one-dimensional-... |

**Lecture 13** Play Video |
**Average velocity for constant acceleration | One-dimensional motion** Calculating average velocity when acceleration is constant. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/one-dimensional-... Missed the previous lesson? https://www.khanacademy.org/science/physics/one-dimensional-... |

**Lecture 14** Play Video |
**Acceleration of aircraft carrier take-off | One-dimensional motion** Using what we know about take-off velocity and runway length to determine acceleration. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/one-dimensional-... Missed the previous lesson? https://www.khanacademy.org/science/physics/one-dimensional-... |

**Lecture 15** Play Video |
**Race cars with constant speed around curve** When acceleration could involve a change in direction and not speed. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/centripetal-forc... Missed the previous lesson? https://www.khanacademy.org/science/physics/forces-newtons-l... |

**Lecture 16** Play Video |
**Introduction to gravity | Centripetal force and gravitation** Basics of gravity and the Law of Universal Gravitation. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/centripetal-forc... Missed the previous lesson? https://www.khanacademy.org/science/physics/centripetal-forc... |

**Lecture 17** Play Video |
**Mass and weight clarification | Centripetal force and gravitation** Difference between mass and weight. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/centripetal-forc... Missed the previous lesson? https://www.khanacademy.org/science/physics/centripetal-forc... |

**Lecture 18** Play Video |
**Gravity for astronauts in orbit | Centripetal force and gravitation** Why do astronauts appear weightless despite being near the Earth? Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/centripetal-forc... Missed the previous lesson? https://www.khanacademy.org/science/physics/centripetal-forc... |

**Lecture 19** Play Video |
**Would a brick or feather fall faster?** What would fall faster on the moon? Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/centripetal-forc... Missed the previous lesson? https://www.khanacademy.org/science/physics/centripetal-forc... |

**Lecture 20** Play Video |
**Deriving displacement as a function of time, acceleration, and initial velocity** Deriving displacement as a function of time, constant acceleration and initial velocity. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/one-dimensional-... Missed the previous lesson? https://www.khanacademy.org/science/physics/one-dimensional-... |

**Lecture 21** Play Video |
**Plotting projectile displacement, acceleration, and velocity** Plotting projectile displacement, acceleration, and velocity as a function to change in time. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/one-dimensional-... Missed the previous lesson? https://www.khanacademy.org/science/physics/one-dimensional-... |

**Lecture 22** Play Video |
**Projectile height given time | One-dimensional motion** Figuring out how high a ball gets given how long it spends in the air. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/one-dimensional-... Missed the previous lesson? https://www.khanacademy.org/science/physics/one-dimensional-... |

**Lecture 23** Play Video |
**Deriving max projectile displacement given time** Deriving a formula for maximum projectile displacement as a function of elapsed time. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/one-dimensional-... Missed the previous lesson? https://www.khanacademy.org/science/physics/one-dimensional-... |

**Lecture 24** Play Video |
**Impact velocity from given height | One-dimensional motion** Determining how fast something will be traveling upon impact when it is released from a given height. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/one-dimensional-... Missed the previous lesson? https://www.khanacademy.org/science/physics/one-dimensional-... |

**Lecture 25** Play Video |
**Visualizing vectors in 2 dimensions | Two-dimensional motion** Visualizing, adding and breaking down vectors in 2 dimensions. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/two-dimensional-... Missed the previous lesson? https://www.khanacademy.org/science/physics/one-dimensional-... |

**Lecture 26** Play Video |
**Projectile at an angle | Two-dimensional motion** Figuring out the horizontal displacement for a projectile launched at an angle. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/two-dimensional-... Missed the previous lesson? https://www.khanacademy.org/science/physics/two-dimensional-... |

**Lecture 27** Play Video |
**Different way to determine time in air | Two-dimensional motion** Another way to determine time in the air given an initial vertical velocity. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/two-dimensional-... Missed the previous lesson? https://www.khanacademy.org/science/physics/two-dimensional-... |

**Lecture 28** Play Video |
**Launching and landing on different elevations | Two-dimensional motion** More complicated example involving launching and landing at different elevations. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/two-dimensional-... Missed the previous lesson? https://www.khanacademy.org/science/physics/two-dimensional-... |

**Lecture 29** Play Video |
**Total displacement for projectile | Two-dimensional motion** Reconstructing the total displacement vector for a projectile. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/two-dimensional-... Missed the previous lesson? https://www.khanacademy.org/science/physics/two-dimensional-... |

**Lecture 30** Play Video |
**Total final velocity for projectile | Two-dimensional motion** Calculating the total final velocity for a projectile landing at a different altitude (mistake near end: I write 29.03 when it should be 26.03 m/s and the final total magnitude should be 26.55 m/s 78.7 degrees below horizontal. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/two-dimensional-... Missed the previous lesson? https://www.khanacademy.org/science/physics/two-dimensional-... |

**Lecture 31** Play Video |
**Correction to total final velocity for projectile** Correction to "Total Final Velocity for Projectile" Video. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/two-dimensional-... Missed the previous lesson? https://www.khanacademy.org/science/physics/two-dimensional-... |

**Lecture 32** Play Video |
**Projectile on an incline | Two-dimensional motion** Challenging problem of a projectile on an inclined plane. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/two-dimensional-... Missed the previous lesson? https://www.khanacademy.org/science/physics/two-dimensional-... |

**Lecture 33** Play Video |
**Unit vectors and engineering notation | Two-dimensional motion** Using unit vectors to represent the components of a vector. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/two-dimensional-... Missed the previous lesson? https://www.khanacademy.org/science/physics/two-dimensional-... |

**Lecture 34** Play Video |
**Optimal angle for a projectile part 1: Components of initial velocity** You want a projectile to fly as far as possible, at which angle should you launch it? We'll start with formulas for the initial velocity. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/two-dimensional-... Missed the previous lesson? https://www.khanacademy.org/science/physics/two-dimensional-... |

**Lecture 35** Play Video |
**Optimal angle for a projectile part 2: Hangtime** Now it's time to think about hangtime for our far-flung projectile. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/two-dimensional-... Missed the previous lesson? https://www.khanacademy.org/science/physics/two-dimensional-... |

**Lecture 36** Play Video |
**Optimal angle for a projectile part 3: Horizontal distance as a function of angle (and speed)** In this video, we'll finish writing the formula for distance as a function of the angle. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/two-dimensional-... Missed the previous lesson? https://www.khanacademy.org/science/physics/two-dimensional-... |

**Lecture 37** Play Video |
**Optimal angle for a projectile part 4: Finding the optimal angle and distance with a bit of calculus** Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/forces-newtons-l... Missed the previous lesson? https://www.khanacademy.org/science/physics/two-dimensional-... |

**Lecture 38** Play Video |
**Normal force and contact force | Forces and Newton's laws of motion** The force that keeps a block of ice from falling towards the center of the earth. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/forces-newtons-l... Missed the previous lesson? https://www.khanacademy.org/science/physics/forces-newtons-l... |

**Lecture 39** Play Video |
**Normal force in an elevator | Forces and Newton's laws of motion** How the normal force changes when an elevator accelerates. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/forces-newtons-l... Missed the previous lesson? https://www.khanacademy.org/science/physics/forces-newtons-l... |

**Lecture 40** Play Video |
**Inclined plane force components | Forces and Newton's laws of motion** Figuring out the components of the force due to gravity that are parallel and perpendicular to the surface of an inclined plane. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/forces-newtons-l... Missed the previous lesson? https://www.khanacademy.org/science/physics/forces-newtons-l... |

**Lecture 41** Play Video |
**Ice accelerating down an incline | Forces and Newton's laws of motion** Figuring out the acceleration of ice down a plane made of ice. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/forces-newtons-l... Missed the previous lesson? https://www.khanacademy.org/science/physics/forces-newtons-l... |

**Lecture 42** Play Video |
**Force of friction keeping the block stationary** Block of wood kept stationary by the force of friction (Correction made in next video). Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/forces-newtons-l... Missed the previous lesson? https://www.khanacademy.org/science/physics/forces-newtons-l... |

**Lecture 43** Play Video |
**Correction to force of friction keeping the block stationary** Correction to Force of Friction Keeping the Block Stationary. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/forces-newtons-l... Missed the previous lesson? https://www.khanacademy.org/science/physics/forces-newtons-l... |

**Lecture 44** Play Video |
**Force of friction keeping velocity constant** Calculating the coefficient of kinetic friction (correction made in next video). Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/forces-newtons-l... Missed the previous lesson? https://www.khanacademy.org/science/physics/forces-newtons-l... |

**Lecture 45** Play Video |
**Intuition on static and kinetic friction comparisons** Why static friction is harder to overcome than kinetic friction. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/forces-newtons-l... Missed the previous lesson? https://www.khanacademy.org/science/physics/forces-newtons-l... |

**Lecture 46** Play Video |
**Static and kinetic friction example | Forces and Newton's laws of motion** Thinking about the coefficients of static and kinetic friction. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/forces-newtons-l... Missed the previous lesson? https://www.khanacademy.org/science/physics/forces-newtons-l... |

**Lecture 47** Play Video |
**Introduction to tension | Forces and Newton's laws of motion** An introduction to tension. Solving for the tension(s) in a set of wires when a weight is hanging from them. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/forces-newtons-l... Missed the previous lesson? https://www.khanacademy.org/science/physics/forces-newtons-l... |

**Lecture 48** Play Video |
**Introduction to tension (part 2) | Forces and Newton's laws of motion** A slightly more difficult tension problem. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/forces-newtons-l... Missed the previous lesson? https://www.khanacademy.org/science/physics/forces-newtons-l... |

**Lecture 49** Play Video |
**Tension in an accelerating system and pie in the face** The second part to the complicated problem. We figure out the tension in the wire connecting the two masses. Then we figure our how much we need to accelerate a pie for it to safely reach a man's face. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/forces-newtons-l... Missed the previous lesson? https://www.khanacademy.org/science/physics/forces-newtons-l... |

**Lecture 50** Play Video |
**Introduction to momentum | Impacts and linear momentum** What momentum is. A simple problem involving momentum. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/linear-momentum/... Missed the previous lesson? https://www.khanacademy.org/science/physics/work-and-energy/... |

**Lecture 51** Play Video |
**Momentum: Ice skater throws a ball | Impacts and linear momentum** A simple conservation of momentum problem involving an ice skater and a ball. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/linear-momentum/... Missed the previous lesson? https://www.khanacademy.org/science/physics/linear-momentum/... |

**Lecture 52** Play Video |
**2-dimensional momentum problem | Impacts and linear momentum** An example of conservation of momentum in two dimensions. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/linear-momentum/... Missed the previous lesson? https://www.khanacademy.org/science/physics/linear-momentum/... |

**Lecture 53** Play Video |
**2-dimensional momentum problem (part 2)** We finish the 2-dimensional momentum problem. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/linear-momentum/... Missed the previous lesson? https://www.khanacademy.org/science/physics/linear-momentum/... |

**Lecture 54** Play Video |
**Introduction to work and energy | Work and energy** Introduction to work and energy. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/work-and-energy/... Missed the previous lesson? https://www.khanacademy.org/science/physics/centripetal-forc... |

**Lecture 55** Play Video |
**Work and energy (part 2) | Work and energy** More on work. Introduction to Kinetic and Potential Energies. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/work-and-energy/... Missed the previous lesson? https://www.khanacademy.org/science/physics/work-and-energy/... |

**Lecture 56** Play Video |
**Conservation of energy | Work and energy** Using the law of conservation of energy to see how potential energy is converted into kinetic energy. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/work-and-energy/... Missed the previous lesson? https://www.khanacademy.org/science/physics/work-and-energy/... |

**Lecture 57** Play Video |
**Work/energy problem with friction | Work and energy** A conservation of energy problem where all of the energy is not conserved. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/work-and-energy/... Missed the previous lesson? https://www.khanacademy.org/science/physics/work-and-energy/... |

**Lecture 58** Play Video |
**Introduction to mechanical advantage | Work and energy** Introduction to simple machines, mechanical advantage and moments. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/work-and-energy/... Missed the previous lesson? https://www.khanacademy.org/science/physics/work-and-energy/... |

**Lecture 59** Play Video |
**Mechanical advantage (part 2) | Work and energy** More on mechanical advantage, levers and moments. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/work-and-energy/... Missed the previous lesson? https://www.khanacademy.org/science/physics/work-and-energy/... |

**Lecture 60** Play Video |
**Mechanical advantage (part 3) | Work and energy** Introduction to pulleys and wedges. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/work-and-energy/... Missed the previous lesson? https://www.khanacademy.org/science/physics/work-and-energy/... |

**Lecture 61** Play Video |
**Center of mass | Impacts and linear momentum** In this video, David solves an example elastic collision problem to find the final velocities using the easier/shortcut approach. Watch the next lesson: https://www.khanacademy.org/science/physics/torque-angular-m... Missed the previous lesson? https://www.khanacademy.org/science/physics/linear-momentum/... |

**Lecture 62** Play Video |
**Introduction to torque | Moments, torque, and angular momentum** An introduction to torque. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/torque-angular-m... Missed the previous lesson? https://www.khanacademy.org/science/physics/torque-angular-m... |

**Lecture 63** Play Video |
**Moments | Moments, torque, and angular momentum** Introduction to moments. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/torque-angular-m... Missed the previous lesson? https://www.khanacademy.org/science/physics/torque-angular-m... |

**Lecture 64** Play Video |
**Moments (part 2) | Moments, torque, and angular momentum** 2 more moment problems. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/torque-angular-m... Missed the previous lesson? https://www.khanacademy.org/science/physics/torque-angular-m... |

**Lecture 65** Play Video |
**Unit vector notation | Two-dimensional motion** Expressing a vector as the scaled sum of unit vectors. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/two-dimensional-... Missed the previous lesson? https://www.khanacademy.org/science/physics/two-dimensional-... |

**Lecture 66** Play Video |
**Unit vector notation (part 2) | Two-dimensional motion** More on unit vector notation. Showing that adding the x and y components of two vectors is equivalent to adding the vectors visually using the head-to-tail method. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/two-dimensional-... Missed the previous lesson? https://www.khanacademy.org/science/physics/two-dimensional-... |

**Lecture 67** Play Video |
**Projectile motion with ordered set notation** Solving the second part to the projectile motion problem (with wind gust) using ordered set vector notation. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/two-dimensional-... Missed the previous lesson? https://www.khanacademy.org/science/physics/two-dimensional-... |

**Lecture 68** Play Video |
**Centripetal force and acceleration intuition** The direction of the force in cases of circular motion at constant speeds. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/centripetal-forc... Missed the previous lesson? https://www.khanacademy.org/science/physics/centripetal-forc... |

**Lecture 69** Play Video |
**Visual understanding of centripetal acceleration formula** Visual understanding of how centripetal acceleration relates to velocity and radius. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/centripetal-forc... Missed the previous lesson? https://www.khanacademy.org/science/physics/centripetal-forc... |

**Lecture 70** Play Video |
**Relationship between angular velocity and speed** How angular velocity relates to speed. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/torque-angular-m... Missed the previous lesson? https://www.khanacademy.org/science/physics/torque-angular-m... |

**Lecture 71** Play Video |
**Calculus proof of centripetal acceleration formula** Proving that a = v^2/r. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/centripetal-forc... Missed the previous lesson? https://www.khanacademy.org/science/physics/centripetal-forc... |

**Lecture 72** Play Video |
**Loop de loop question | Centripetal force and gravitation** Asks students to find the minimum speed necessary to complete the loop de loop. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/centripetal-forc... Missed the previous lesson? https://www.khanacademy.org/science/physics/centripetal-forc... |

**Lecture 73** Play Video |
**Loop de loop answer part 1 | Centripetal force and gravitation** Figuring out the minimum speed at the top of the loop de loop to stay on the track. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/centripetal-forc... Missed the previous lesson? https://www.khanacademy.org/science/physics/centripetal-forc... |

**Lecture 74** Play Video |
**Loop de loop answer part 2 | Centripetal force and gravitation** Figuring out the car's average speed while completing the loop de loop. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/centripetal-forc... Missed the previous lesson? https://www.khanacademy.org/science/physics/centripetal-forc... |

**Lecture 75** Play Video |
**Acceleration due to gravity at the space station** What is the acceleration due to gravity at the space station. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/centripetal-forc... Missed the previous lesson? https://www.khanacademy.org/science/physics/centripetal-forc... |

**Lecture 76** Play Video |
**Space station speed in orbit | Centripetal force and gravitation** Speed necessary for the space station to stay in orbit. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/centripetal-forc... Missed the previous lesson? https://www.khanacademy.org/science/physics/centripetal-forc... |

**Lecture 77** Play Video |
**Conservation of angular momemtum** Angular momentum is constant when there is no net torque. More free lessons at: http://www.khanacademy.org/video?v=s_R8d3isJDA |

**Lecture 78** Play Video |
**Introduction to Newton's law of gravitation** A little bit on gravity. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/centripetal-forc... Missed the previous lesson? https://www.khanacademy.org/science/physics/centripetal-forc... |

**Lecture 79** Play Video |
**Gravitation (part 2) | Centripetal force and gravitation** A little bit more on gravity. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/work-and-energy/... Missed the previous lesson? https://www.khanacademy.org/science/physics/centripetal-forc... |

**Lecture 80** Play Video |
**Intro to springs and Hooke's law | Work and energy** Introduction to Hooke's Law. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/work-and-energy/... Missed the previous lesson? https://www.khanacademy.org/science/physics/work-and-energy/... |

**Lecture 81** Play Video |
**Potential energy stored in a spring | Work and energy** Work needed to compress a spring is the same thing as the potential energy stored in the compressed spring. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/work-and-energy/... Missed the previous lesson? https://www.khanacademy.org/science/physics/work-and-energy/... |

**Lecture 82** Play Video |
**Spring potential energy example (mistake in math)** A spring, a frozen loop-d-loop and more! (See if you can find the mistake I made and get the right answer!). Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/work-and-energy/... Missed the previous lesson? https://www.khanacademy.org/science/physics/work-and-energy/... |

**Lecture 83** Play Video |
**Introduction to harmonic motion | Oscillatory motion** Intuition behind the motion of a mass on a spring (some calculus near the end). Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/oscillatory-moti... Missed the previous lesson? https://www.khanacademy.org/science/physics/torque-angular-m... |

**Lecture 84** Play Video |
**Harmonic motion part 2 (calculus) | Oscillatory motion** We test whether Acos(wt) can describe the motion of the mass on a spring by substituting into the differential equation F=-kx. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/oscillatory-moti... Missed the previous lesson? https://www.khanacademy.org/science/physics/oscillatory-moti... |

**Lecture 85** Play Video |
**Harmonic motion part 3 (no calculus) | Oscillatory motion** Figuring out the period, frequency, and amplitude of the harmonic motion of a mass attached to a spring. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/fluids/density-a... Missed the previous lesson? https://www.khanacademy.org/science/physics/oscillatory-moti... |

**Lecture 86** Play Video |
**Pressure and Pascal's principle (part 1) | Fluids** Sal explains the difference between liquids and gasses (both fluids). He then starts a calculation of the work done on a liquid in a U-shaped container. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/fluids/density-a... Missed the previous lesson? https://www.khanacademy.org/science/physics/fluids/density-a... |

**Lecture 87** Play Video |
**Pressure and Pascal's principle (part 2) | Fluids** Sal finishes the calculation or work to determine the mechanical advantage in a U-shaped tube. He also explains pressure and Pascal's Principal. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/fluids/density-a... Missed the previous lesson? https://www.khanacademy.org/science/physics/fluids/density-a... |

**Lecture 88** Play Video |
**Pressure at a depth in a fluid | Fluids** Sal finishes the calculation or work to determine the mechanical advantage in a U-shaped tube. He also explains pressure and Pascal's Principal. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/fluids/density-a... Missed the previous lesson? https://www.khanacademy.org/science/physics/fluids/density-a... |

**Lecture 89** Play Video |
**Finding height of fluid in a barometer | Fluids** Using our understanding of fluid pressure to figure out the height of a column of mercury. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/fluids/buoyant-f... Missed the previous lesson? https://www.khanacademy.org/science/physics/fluids/density-a... |

**Lecture 90** Play Video |
**Archimedes principle and buoyant force | Fluids** Introduction to Archimedes' principle and buoyant force. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/fluids/buoyant-f... Missed the previous lesson? https://www.khanacademy.org/science/physics/fluids/density-a... |

**Lecture 91** Play Video |
**Buoyant force example problems | Fluids** A couple of problems involving Archimedes' principle and buoyant forces. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/fluids/fluid-dyn... Missed the previous lesson? https://www.khanacademy.org/science/physics/fluids/buoyant-f... |

**Lecture 92** Play Video |
**Volume flow rate and equation of continuity | Fluids** Sal introduces the notion of moving fluids and laminar flow. Then he uses the incompressibility of a liquid to show that the volume flow rate (flux) must remain constant. Sal then derives the equation of continuity in terms of the area and speed. . Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/fluids/fluid-dyn... Missed the previous lesson? https://www.khanacademy.org/science/physics/fluids/buoyant-f... |

**Lecture 93** Play Video |
**Bernoulli's equation (part 1) | Fluids** This is the first of two videos where Sal derives Bernoulli's equation. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/fluids/fluid-dyn... Missed the previous lesson? https://www.khanacademy.org/science/physics/fluids/fluid-dyn... |

**Lecture 94** Play Video |
**Bernoulli's equation (part 2) | Fluids** This is the second of two videos where Sal derives Bernoulli's equation. In the second half of the video Sal also begins an example problem where liquid exits a hole in a container. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/fluids/fluid-dyn... Missed the previous lesson? https://www.khanacademy.org/science/physics/fluids/fluid-dyn... |

**Lecture 95** Play Video |
**Bernoulli's equation (part 3) | Fluids** Sal finishes the example problem where liquid exits a hole in a container. . Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/fluids/fluid-dyn... Missed the previous lesson? https://www.khanacademy.org/science/physics/fluids/fluid-dyn... |

**Lecture 96** Play Video |
**Bernoulli's equation (part 4) | Fluids** Clarification of, and more thoughts on, the Bernoulli's equation example problem where liquid exits a hole in a container. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/fluids/fluid-dyn... Missed the previous lesson? https://www.khanacademy.org/science/physics/fluids/fluid-dyn... |

**Lecture 97** Play Video |
**Bernoulli's example problem | Fluids** Sal solves a Bernoulli's equation example problem where fluid is moving through a pipe of varying diameter. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/fluids/fluid-dyn... Missed the previous lesson? https://www.khanacademy.org/science/physics/fluids/fluid-dyn... |

**Lecture 98** Play Video |
**Thermodynamics part 1: Molecular theory of gases** Intuition of how gases generate pressure in a container and why pressure x volume is proportional to the combined kinetic energy of the molecules in the volume. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/thermodynamics/t... Missed the previous lesson? https://www.khanacademy.org/science/physics/fluids/fluid-dyn... |

**Lecture 99** Play Video |
**Thermodynamics part 2: Ideal gas law | Thermodynamics** Intuition of how gases generate pressure in a container and why pressure x volume is proportional to the combined kinetic energy of the molecules in the volume. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/thermodynamics/t... Missed the previous lesson? https://www.khanacademy.org/science/physics/thermodynamics/t... |

**Lecture 100** Play Video |
**Thermodynamics part 3: Kelvin scale and Ideal gas law example** Sal makes the case for the Kelvin scale of temperature and absolute zero by showing that temperature is proportional to kinetic energy. Then he explains that you need to use the Kelvin scale in the ideal gas law. To finish he does a sample ideal gas law problem. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/thermodynamics/t... Missed the previous lesson? https://www.khanacademy.org/science/physics/thermodynamics/t... |

**Lecture 101** Play Video |
**Thermodynamics part 4: Moles and the ideal gas law** Sal explains the concept of a mole. Then he derives the molar version of the ideal gas law PV=nRT, where the gas constant R=8.31 J/molK. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/thermodynamics/t... Missed the previous lesson? https://www.khanacademy.org/science/physics/thermodynamics/t... |

**Lecture 102** Play Video |
**Thermodynamics part 5: Molar ideal gas law problem** Sal uses the molar version of the ideal gas law to solve for the number of moles in a gas. He also shows how to convert this answer into number of molecules using Avogadro's number. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/thermodynamics/t... Missed the previous lesson? https://www.khanacademy.org/science/physics/thermodynamics/t... |

**Lecture 103** Play Video |
**Electrostatics (part 1): Introduction to Charge and Coulomb's Law** Introduction to Charge and Coulomb's Law (video from May 2008 that I forgot to upload) More free lessons at: http://www.khanacademy.org/video?v=NXMgvrS8Gr8 |

**Lecture 104** Play Video |
**Electric field | Electric charge, electric force, and voltage** We can think of the forces between charges as something that comes from a property of space. That property is called the electric field. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/electric-charge-... Missed the previous lesson? https://www.khanacademy.org/science/physics/electric-charge-... |

**Lecture 105** Play Video |
**Proof: Field from infinite plate (part 1) | Electrostatics | Electrical engineering** Advanced proof of the formula for the electric field generated by a uniformly charged, infinite plate. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/electrical-engineering/e... Missed the previous lesson? https://www.khanacademy.org/science/electrical-engineering/e... Electrical engineering on Khan Academy: A summary of the math and science preparation that will help you have the best experience with electrical engineering taught on Khan Academy. Become familiar with engineering numbers and notation, and learn about the two most important electrical quantities: current and voltage. Subscribe to Khan Academy’s Electrical Engineering channel: https://www.youtube.com/channel/UC8JT97hQjMVWeO0B-x8eVxQ?sub... |

**Lecture 106** Play Video |
**Proof: Field from infinite plate (part 2) | Electrostatics | Electrical engineering** We see that the infinite, uniformly charged plate generates a constant electric field (independent of the height above the plate). Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/electrical-engineering/e... Missed the previous lesson? https://www.khanacademy.org/science/electrical-engineering/e... Electrical engineering on Khan Academy: A summary of the math and science preparation that will help you have the best experience with electrical engineering taught on Khan Academy. Become familiar with engineering numbers and notation, and learn about the two most important electrical quantities: current and voltage. Subscribe to Khan Academy’s Electrical Engineering channel: https://www.youtube.com/channel/UC8JT97hQjMVWeO0B-x8eVxQ?sub... |

**Lecture 107** Play Video |
**Electric potential energy | Electrostatics | Electrical engineering** Introduction to electric potential energy. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/electrical-engineering/r... Missed the previous lesson? https://www.khanacademy.org/science/electrical-engineering/e... Electrical engineering on Khan Academy: A summary of the math and science preparation that will help you have the best experience with electrical engineering taught on Khan Academy. Become familiar with engineering numbers and notation, and learn about the two most important electrical quantities: current and voltage. Subscribe to Khan Academy’s Electrical Engineering channel: https://www.youtube.com/channel/UC8JT97hQjMVWeO0B-x8eVxQ?sub... |

**Lecture 108** Play Video |
**Electric potential energy (part 2-- involves calculus)** Electric potential energy difference in a varying field. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/electric-charge-... Missed the previous lesson? https://www.khanacademy.org/science/physics/electric-charge-... |

**Lecture 109** Play Video |
**Voltage | Electric charge, electric force, and voltage** Sal explains the difference between electrical potential (voltage) and electrical potential energy. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/electric-charge-... Missed the previous lesson? https://www.khanacademy.org/science/physics/electric-charge-... |

**Lecture 110** Play Video |
**Capacitance | Circuits** Introduction to the capacitance of a two place capacitor. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/circuits-topic/c... Missed the previous lesson? https://www.khanacademy.org/science/physics/circuits-topic/c... |

**Lecture 111** Play Video |
**Introduction to circuits and Ohm's law | Circuits** Introduction to electricity, circuits, current, and resistance. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/circuits-topic/c... Missed the previous lesson? https://www.khanacademy.org/science/physics/electric-charge-... |

**Lecture 112** Play Video |
**Resistors in series | Circuits** Resistors that come one after another. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/circuits-topic/c... Missed the previous lesson? https://www.khanacademy.org/science/physics/circuits-topic/c... |

**Lecture 113** Play Video |
**Resistors in parallel | Circuits** Resistors that run alongside each other. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/circuits-topic/c... Missed the previous lesson? https://www.khanacademy.org/science/physics/circuits-topic/c... |

**Lecture 114** Play Video |
**Example: Analyzing a more complex resistor circuit** A hairy resistance problem. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/circuits-topic/c... Missed the previous lesson? https://www.khanacademy.org/science/physics/circuits-topic/c... |

**Lecture 115** Play Video |
**Cross product 1 | Magnetic forces, magnetic fields, and Faraday's law** Introduction to the cross product. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/magnetic-forces-... Missed the previous lesson? https://www.khanacademy.org/science/physics/magnetic-forces-... |

**Lecture 116** Play Video |
**Cross product 2 | Magnetic forces, magnetic fields, and Faraday's law** A little more intuition on the cross product. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/magnetic-forces-... Missed the previous lesson? https://www.khanacademy.org/science/physics/magnetic-forces-... |

**Lecture 117** Play Video |
**Cross product and torque | Moments, torque, and angular momentum** The cross product and the direction of torque. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/oscillatory-moti... Missed the previous lesson? https://www.khanacademy.org/science/physics/torque-angular-m... |

**Lecture 118** Play Video |
**Introduction to magnetism** An introduction to magnetism. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/magnetic-forces-... Missed the previous lesson? https://www.khanacademy.org/science/physics/circuits-topic/c... |

**Lecture 119** Play Video |
**Magnetic force on a charge** Sal shows how to find the size and direction of the magnetic force using F=qvB and the right hand rule. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/magnetic-forces-... Missed the previous lesson? https://www.khanacademy.org/science/physics/magnetic-forces-... |

**Lecture 120** Play Video |
**Magnetic force on a proton example (part 1)** Sal does an example problem to determine the size and direction of the magnetic force on a proton moving through a magnetic field. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/magnetic-forces-... Missed the previous lesson? https://www.khanacademy.org/science/physics/magnetic-forces-... |

**Lecture 121** Play Video |
**Magnetic force on a proton example (part 2)** Sal determines the radius of the circle traveled by the proton in the previous example by using the formula for centripetal acceleration. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/magnetic-forces-... Missed the previous lesson? https://www.khanacademy.org/science/physics/magnetic-forces-... |

**Lecture 122** Play Video |
**Magnetic force on a current carrying wire** Sal derives the formula F=ILB to determine the force on a current carrying wire. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/magnetic-forces-... Missed the previous lesson? https://www.khanacademy.org/science/physics/magnetic-forces-... |

**Lecture 123** Play Video |
**Magnetic field created by a current carrying wire** See how a wire carrying a current creates a magnetic field. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/magnetic-forces-... Missed the previous lesson? Watch the next lesson: https://www.khanacademy.org/science/physics/magnetic-forces-... |

**Lecture 124** Play Video |
**Magnetic force between two currents going in the same direction** Sal shows how to determine the magnetic force between two currents going in the same direction. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/magnetic-forces-... Missed the previous lesson? https://www.khanacademy.org/science/physics/magnetic-forces-... |

**Lecture 125** Play Video |
**Magnetic force between two currents going in opposite directions** Sal shows how to determine the magnetic force between two currents going in opposite directions. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/magnetic-forces-... Missed the previous lesson? https://www.khanacademy.org/science/physics/magnetic-forces-... |

**Lecture 126** Play Video |
**Electric motors (part 1)** Sal shows that there will be a net torque on a loop of current in a wire. Sal shows that this net torque will cause the loop to rotate. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/magnetic-forces-... Missed the previous lesson? https://www.khanacademy.org/science/physics/magnetic-forces-... |

**Lecture 127** Play Video |
**Electric motors (part 2)** Sal shows that a commutator can be used in order to keep the loop of wire rotating in the magnetic field. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/magnetic-forces-... Missed the previous lesson? https://www.khanacademy.org/science/physics/magnetic-forces-... |

**Lecture 128** Play Video |
**Electric motors (part 3)** Sal finishes the explanation of how a commutator will allow a loop of wire to continue spinning in a magnetic field, thereby allowing it to work as an electric motor. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/magnetic-forces-... Missed the previous lesson? https://www.khanacademy.org/science/physics/magnetic-forces-... |

**Lecture 129** Play Video |
**Induced current in a wire** Sal determines the current and EMF induced in a wire pulled through a magnetic field. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/magnetic-forces-... Missed the previous lesson? https://www.khanacademy.org/science/physics/magnetic-forces-... |

**Lecture 130** Play Video |
**The dot product | Magnetic forces, magnetic fields, and Faraday's law** Introduction to the vector dot product. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/magnetic-forces-... Missed the previous lesson? https://www.khanacademy.org/science/physics/magnetic-forces-... |

**Lecture 131** Play Video |
**Dot vs. cross product** Understanding the differences between the dot and cross products. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/magnetic-forces-... Missed the previous lesson? https://www.khanacademy.org/science/physics/magnetic-forces-... |

**Lecture 132** Play Video |
**Calculating dot and cross products with unit vector notation** Calculating the dot and cross products when vectors are presented in their x, y, and z (or i,j, and k) components. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/magnetic-forces-... Missed the previous lesson? https://www.khanacademy.org/science/physics/magnetic-forces-... |

**Lecture 133** Play Video |
**Introduction to waves | Mechanical waves and sound** Introduction to transverse and longitudinal waves. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/mechanical-waves... Missed the previous lesson? https://www.khanacademy.org/science/physics/magnetic-forces-... |

**Lecture 134** Play Video |
**Amplitude, period, frequency and wavelength of periodic waves** Amplitude, period, frequency and wavelength of periodic waves. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/mechanical-waves... Missed the previous lesson? https://www.khanacademy.org/science/physics/mechanical-waves... |

**Lecture 135** Play Video |
**Introduction to the doppler effect | Mechanical waves and sound** Introduction to the Doppler Effect. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/mechanical-waves... Missed the previous lesson? https://www.khanacademy.org/science/physics/mechanical-waves... |

**Lecture 136** Play Video |
**Doppler effect formula for observed frequency** Let's derive the formula for how the perceived frequency of a sound changes when its source is moving toward you. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/mechanical-waves... Missed the previous lesson? https://www.khanacademy.org/science/physics/mechanical-waves... |

**Lecture 137** Play Video |
**Doppler effect formula when source is moving away** Let's look at the case where the source is moving away from the listener. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/mechanical-waves... Missed the previous lesson? https://www.khanacademy.org/science/physics/mechanical-waves... |

**Lecture 138** Play Video |
**When the source and the wave move at the same velocity** What happens when both the listener and the source are moving together? Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/mechanical-waves... Missed the previous lesson? https://www.khanacademy.org/science/physics/mechanical-waves... |

**Lecture 139** Play Video |
**Mach numbers | Mechanical waves and sound** We can measure speeds relative to the speed of sound. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/mechanical-waves... Missed the previous lesson? https://www.khanacademy.org/science/physics/mechanical-waves... |

**Lecture 140** Play Video |
**Specular and diffuse reflection | Geometric optics** Specular and Diffuse Reflection. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/geometric-optics... Missed the previous lesson? https://www.khanacademy.org/science/physics/light-waves/inte... |

**Lecture 141** Play Video |
**Specular and diffuse reflection 2 | Geometric optics** Specular and Diffuse Reflection 2. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/geometric-optics... Missed the previous lesson? https://www.khanacademy.org/science/physics/geometric-optics... |

**Lecture 142** Play Video |
**Refraction and Snell's law | Geometric optics** Refraction and Snell's Law. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/geometric-optics... Missed the previous lesson? https://www.khanacademy.org/science/physics/geometric-optics... |

**Lecture 143** Play Video |
**Refraction in water | Geometric optics** Refraction in Water. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/geometric-optics... Missed the previous lesson? https://www.khanacademy.org/science/physics/geometric-optics... |

**Lecture 144** Play Video |
**Snell's law example 1 | Geometric optics** Snell's Law Example 1. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/geometric-optics... Missed the previous lesson? https://www.khanacademy.org/science/physics/geometric-optics... |

**Lecture 145** Play Video |
**Snell's law example 2 | Geometric optics** Snell's Law Example 2. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/geometric-optics... Missed the previous lesson? https://www.khanacademy.org/science/physics/geometric-optics... |

**Lecture 146** Play Video |
**Total internal reflection | Geometric optics** Critical incident angle and total internal reflection. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/geometric-optics... Missed the previous lesson? https://www.khanacademy.org/science/physics/geometric-optics... |

**Lecture 147** Play Video |
**Virtual image | Geometric optics** Virtual Image. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/geometric-optics... Missed the previous lesson? https://www.khanacademy.org/science/physics/geometric-optics... |

**Lecture 148** Play Video |
**Parabolic mirrors and real images | Geometric optics** Parabolic Mirrors and Real Images. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/geometric-optics... Missed the previous lesson? https://www.khanacademy.org/science/physics/geometric-optics... |

**Lecture 149** Play Video |
**Parabolic mirrors 2 | Geometric optics** Parabolic Mirrors 2. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/geometric-optics... Missed the previous lesson? https://www.khanacademy.org/science/physics/geometric-optics... |

**Lecture 150** Play Video |
**Convex parabolic mirrors | Geometric optics** Convex Parabolic Mirrors. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/geometric-optics... Missed the previous lesson? https://www.khanacademy.org/science/physics/geometric-optics... |

**Lecture 151** Play Video |
**Convex lenses | Geometric optics** Convex Lenses. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/geometric-optics... Missed the previous lesson? https://www.khanacademy.org/science/physics/geometric-optics... |

**Lecture 152** Play Video |
**Convex lens examples | Geometric optics** Convex Lens Examples. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/geometric-optics... Missed the previous lesson? https://www.khanacademy.org/science/physics/geometric-optics... |

**Lecture 153** Play Video |
**Concave lenses | Geometric optics** Concave Lenses. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/geometric-optics... Missed the previous lesson? https://www.khanacademy.org/science/physics/geometric-optics... |

**Lecture 154** Play Video |
**Object image and focal distance relationship (proof of formula)** Object Image and Focal Distance Relationship (Proof of Formula). Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/geometric-optics... Missed the previous lesson? https://www.khanacademy.org/science/physics/geometric-optics... |

**Lecture 155** Play Video |
**Object image height and distance relationship | Geometric optics** Object Image Height and Distance Relationship. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/geometric-optics... Missed the previous lesson? https://www.khanacademy.org/science/physics/geometric-optics... |

**Lecture 156** Play Video |
**Viewing g as the value of Earth's gravitational field near the surface** Viewing g as the value of Earth's gravitational field near the surface rather than the acceleration due to gravity near Earth's surface for an object in freefall. Created by Sal Khan. Watch the next lesson: https://www.khanacademy.org/science/physics/one-dimensional-... Missed the previous lesson? https://www.khanacademy.org/science/physics/one-dimensional-... |