  Fluids and Waves with Lab Demonstrations

Video Lectures

Displaying all 29 video lectures.
 Lecture 1 Play Video Elasticity 1: Stress and StrainThis lecture introduces the concept of elasticity and covers the definitions of different types of mechanical stress and strain. Lecture 2 Play Video Elasticity 2: Young's ModulusThis lecture shows how to measure Young's Modulus for an elastic band. This includes examples of how to calculate experimental uncertainties using partial derivatives which is a good introduction to their use for later in the course with waves. Lecture 3 Play Video Elasticity 3: Moduli of ElasticityThis lecture extends the concept of Young's Modulus to the general case: Modulus of Elasticity. Moduli for the different types of stress and strain are discussed an a new type of stress, bulk stress, is introduced along with it's associated bulk strain and bulk modulus. Lecture 4 Play Video Elasticity 4: Elastic LimitsThis lecture returns to the Young's Modulus elastic band experiment to demonstrate the effect of hysteresis when the band is unloaded. The elastic limit, plastic deformation and breaking stress are described in the context of a stress-strain plot. Finally the concepts of ductile and brittle materials are discussed. Lecture 5 Play Video Fluid Statics 1: Pressure and DensityIn this lecture we introduce the concepts of pressure and density for a fluid and demonstrate how pressure acts in all directions. Lecture 6 Play Video Fluid Statics 2: Static PressureThis lecture starts with the derivation of the static pressure at depth in a fluid and the behaviour of fluids which results from that. The lecture concludes with Pascal's Law and a demonstration of how hydraulics work. Lecture 7 Play Video Fluid Statics 3: Pressure GaugesThis lecture describes how we can use the static pressure of a liquid to convert pressure measurements into length measurements. We also see that sucking water out of a bottle has its limits! Lecture 8 Play Video Fluid Statics 4: Buoyancy ForceIn this final lecture on fluid statics we discuss the buoyancy force which an object immersed in a fluid is subject to and which was first quantified by Archimedes. Lecture 9 Play Video Fluid Dynamics 1: Fluid FlowFlow is a defining characteristic of a fluid. This lecture introduces the concept of surface tension and then covers the types of of fluid flow using examples both in nature and the lab. To conclude the continuity equation is introduced and used to characterize the flow of incompressible liquid in a pipe. Lecture 10 Play Video Fluid Dynamics 2: Bernoulli's EquationStarting with conservation of energy for fluid flows we derive Bernoulli's equation which is then demonstrated in some fun, and counterintuitive experiments - some of which you can easily try for yourselves. To conclude Torricelli's law is also derived and demonstrated. Lecture 11 Play Video Fluid Dynamics 3: ViscosityTo conclude our discussion of fluid dynamics we introduce the concept of viscosity, starting with the definition of shear, or dynamic viscosity and its effects of fluid flow in a pipe. Viscous flow in the simplest possible situation, a long, straight circular pipe is discussed in terms of Poiseuille's law and the lecture concludes with a demonstration of this. Lecture 12 Play Video Oscillations 1: Derivation of Simple Harmonic MotionThis video introduces the parameters used to describe an oscillator and, using the case of a mass-spring systems, derives the solution for the displacement of the mass as a function of time. Lecture 13 Play Video Oscillations 2: SHM ParametersHere we relate the solution for the displacement with the physical parameters of simple harmonic motion and demonstrate that the solution is consistent with experiment. Lecture 14 Play Video Oscillations 3: PhasorsThis video demonstrates that the displacement of a simple harmonic oscillator can be written down in several, mathematical equivalent ways including a rotating vector in the complex plane called a phasor. It also shows the solution for a vertical mass-spring system. Lecture 15 Play Video Oscillations 4: Kinematics and EnergyThis video shows how to derive the velocity and acceleration of a simple harmonic oscillator. We then use the velocity and displacement to calculate the kinetic and potential energy of the oscillator and show that the total is constant. Lecture 16 Play Video Oscillations 5: PendulumsIn this lecture we solve for the motion of simple and compound pendulums and demonstrate that, for small amplitudes, they undergo simple harmonic motion. Lecture 17 Play Video Oscillations 6: Damped OscillatorsThis lecture solves for the motion of a harmonic oscillator which has a damping force applied. The result solutions are classified into one of three types and the motion for each discussed. Lecture 18 Play Video Oscillations 7: Driven OscillatorsIn this video we solve for the situation where a periodic force is applied to a damped, harmonic oscillator. The resulting equation of motion is solved to determine the amplitude and phase of the oscillator's displacement. Lecture 19 Play Video Oscillations 8: ResonanceBuilding on the solution for the amplitude of a driven harmonic oscillator we show that this leads to the phenomenon of resonance. This is demonstrated for a simple, mechanical oscillator as well as an AC circuit and at a fundamental particle level with the production of Z bosons. Lecture 20 Play Video Waves 1: Wave Types and PropertiesIntroduction to the phenomenon of waves. This lecture introduces the basic properties of waves such as frequency, wavelength and wave number and shows how these are related to the phase velocity of the wave. Lecture 21 Play Video Waves 2: The Wave EquationShows the derivation of the wave equation from first principles. Lecture 22 Play Video Waves 3: Solving the Wave EquationSolves the wave equation using the separation of variables technique to derive the mathematical description of a wave. It also introduces the concept of Fourier transforms to show how we can make different wave shapes from sine waves. Lecture 23 Play Video Waves 4: Waves on a StringThis lecture demonstrates how to derive the wave equation for waves on a string and uses it to calculate the phase velocity of this type of wave. It includes some qualitative demonstrations on how the phase velocity changes with both the mass per unit length of the string and the tension in it. Lecture 24 Play Video Waves 5: Acoustic WavesThis lecture shows how to derive the wave equation for an acoustic wave both as a pressure wave and as a displacement wave and this is used to calculate the phase velocity. The phase difference between the displacement and pressure deviation is also calculated. Lecture 25 Play Video Waves 6: Wave IntensityThis video introduces the concept of wave intensity for 3D waves by considering the wave power of an acoustic wave. Applying conservation of energy shows how the intensity decreases with distance from the source and that the relationship is different for both surface and bulk waves and how knowing this can lead to some amazing measurements. Lecture 26 Play Video Waves 7: SuperpositionThis lecture discusses what happens when two waves are super imposed on each other. Starting with a demonstration of two pulses on a string the observed behaviour is related to the wave equation. The discussion is then broadened to reflection of waves at boundaries and the general principle of superposition and phase difference is included. Lecture 27 Play Video Waves 8: InterferenceIn this lecture we will show what happens when waves interact from two identical sources of waves. The phenomenon of beats, from two sources of slightly different frequencies will also be demonstrated. Lecture 28 Play Video Waves 9: Standing WavesThis lecture covers the important topic of standing waves which is the physics behind not only music but atoms as well. Standing waves on strings an pipes will be derived and demonstrated. Lecture 29 Play Video Waves 10: The Doppler EffectThis video introduces the doppler effect which is cause by the motion of a wave source and observer relative to the medium of the wave. The relativistic doppler effect for EM waves will also be derived.