Oscillations and waves
Wave phenomena
On this page we will examine the wave phenomena of reflection, refraction, interference, diffraction and polarisation, as well as the concept of standing (or stationary) waves. To show these in a visual way we will use a ripple tank simulation. Wave…
Atomic, nuclear and particles
Wave particle duality
…ton scattering and pair production that electromagnetic radiation can have quantum properties indicates that matter may have wave properties. Here we will consider this possibility. Key Concepts Electron diffraction When electrons are passed through…
Oscillations and waves
Standing waves on a string
It is easy to observe the wave motion in a string but it doesn´t tell the whole story of wave properties. A string wave can't diffract or refract. Sometimes simple explanations cause misunderstandings. Here a string wave is polarised by a narrow…
Oscillations and waves
Single slit diffraction
Diffraction is the spreading out of a wave when passing through a gap in a boundary. It is optimised when the width of the gap is similar in magnitude to the wavelength of the wave. With a small enough gap we can diffract visible light. X-rays have a…
Oscillations and waves
Waves
A wave is a transfer of energy or information using oscillations of a medium, without moving the particles of the medium themselves. Waves can be modelled mathematically and have a number of different properties. Key Concepts Wave phenomena All wave…
Oscillations and waves
Graphical representation of waves
…d time. However, take care to realise that a graph is not a picture of a wave. Since there is no energy transfer, a pendulum wave isn't really a wave... but it looks impressive! Key Concepts A wave is made of a series of out of phase oscillation…
Oscillations and waves
Sound
We represent a sound wave by drawing lines like the coils of a slinky spring. But we should remember that, although layers of air oscillate, the individual atoms do not. Key Concepts Pressure wave A sound wave is the propagation of changes in pressu…
Oscillations and waves
Light
…to study the next section on electromagnetism. However, it is enough to use what we know about other waves to understand the wave nature of light. Key Concepts Electromagnetic spectrum Light is part of the electromagnetic spectrum. Electromagnetic wa…
Why two lamps don't interfere
…wo lamps interfere with each other? The reason is that they are not coherent. Each lamp is made of a large number of atomic wave sources that have random phase, the wavefront produced from each lamp changes with time so any interference effect will…
Rectification
Making a full wave rectifier can be difficult but it's simpler if you build it in two stages. Here LEDs are used to bring the circuit to life. First a line of 3 LEDs are connected in the same direction so they all come on when the current is in the…
Atomic, nuclear and particles
AHL Quantum
…n opposite directions to conserve momentum). Electrons as waves The quantum nature of light indicates that there must be a wave nature of matter. Indeed, electrons are diffracted and produce interference patterns when passed through a sheet of grap…
Atomic, nuclear and particles
Atomic models
…tanding the probability of an electron's position is a standing wave. Just as an electron cannot move outside an atom, a wave cannot move from a string clamped at both ends. A standing wave may only oscillate at particular harmonic frequencies; a…
Atomic, nuclear and particles
Photoelectric effect and photons
…on depends not on intensity but frequency. Key Concepts Photoelectric effect There is a significant body of evidence for the wave model of light including interference and diffraction. Reflection and refraction are also wave properties, but are not e…
Oscillations and waves
Introduction to waves
…. Key Concepts Properties and quantities The kinetic energy of a particle travels with the particle, whereas the energy in a wave spreads out. Quantities used to describe waves include: Wavelength Frequency Wave speed Wave propagation A wavefront…
Oscillations and waves
Doppler effect
The Doppler effect is the first wave phenomenon that we consider in this Additional Higher Level topic. It is a change in frequency in observed sound caused by relative motion between the source, the observer or the medium. Here we will learn how to…
Electricity and magnetism
Diodes and rectification
…deal diode would have zero resistance in one direction and infinite) resistance in the other. Stages in rectification Half wave The simplest form of rectification is the insertion of a diode in the series circuit. All current in the forward directi…
Oscillations and waves
AHL Waves
…e source moving towards the observer A sonic boom is produced when the relative speed of the source exceeds the speed of the wave in the medium. The Doppler effect affects light waves and can be used to determine the relative speeds of objects in the…
Oscillations and waves
…een source and observer. Find out more. What is meant by diffraction and interference? Diffraction is the spreading out of a wave when passing through a gap in a boundary. Find out more. Interference is when two waves of the same type meet and they c…
Energy production
Renewable sources I
…a river. The flow of water can be used to drive turbines, which are positioned horiztontally. Note that this is different to wave power, where the crashing waves directly strike turbines on a vertical plane. Essentials Almost all the renewable sour…
Oscillations and waves
Thin film interference
…ky concept involving reflection, refraction and phase changes at interfaces. Key Concepts Phase changes at interfaces When a wave reflects off a loose boundary, it experiences no phase change. However, when a wave reflects off a fixed boundary, it ex…
Swimming pool investigations
…nalysis of the motion of sinking objects. Analysis of the motion of buoyant objects. The speed of waves at different depths. Wave interference. Wave amplitude and distance from a point source. Centripetal force in the slide at different velocities. U…
Electricity and magnetism
AHL EM induction
…ary coil (A) Essentials Rectification Alternating current can be converted into direct current by rectification: In half wave rectification, a diode is inserted. Current will only pass in forward bias. In full wave rectification, two diode pathwa…
Atomic, nuclear and particles
AHL Nuclear radius
…of electrons and the angle of the first minimum intensity in the scattering pattern: Electrons may interact with matter as a wave when the nucleus is comparable in size to the de Broglie wavelength (Wave particle duality) The diffraction pattern arou…
Daily IA
…ts. however, if a laser is shone onto the surface its reflection on a nearby wall moves up and down, if the amplitude of the wave is increased the amplitude of the reflected laser also increases so this can be used to measure the wave amplitude. The…
IA 2022
…d by the tension of a string? Thalia: What is the relationship of the distance between the loops of a slinky spring and the wave speed? Dickson: What is the relation between the spring constant and the maximum force exerted when extended by a body…
Basics
…d as the ratio of the mass of a body to its volume. Find out more. What is intensity of light in physics? The intensity of a wave is the power incident on a surface per unit area. Find out more.…
Basics
Greek alphabet
…iameter) Ρ ρ rho Density Σ σ, ς sigma Sum of [quantity] Τ τ tau Lepton Υ υ upsilon Φ φ phi Magnetic flux Χ χ chi Ψ ψ psi Wave function Ω ω omega Ohm Test Yourself Use flashcards to practise your recall. Flashcards Topics: Greek alphabet Levels:…
Oscillations and waves
Phase
…r at different times. It is important to understand the concept of phase before starting the Waves section. In short: a full wave cycle consists of 2π radians. Key Concepts The oscillations of two pendula can be represented by two sine or cosine curv…
Exam questions
HL practice paper 2
…ncy and amplitude Travelling in opposite directions Interfere with each other The most regular occurence of this is a single wave reflecting back onto itself. Node: Point that has zero amplitude Wavelength (λ): The distance between two equivalent poi…
Atomic, nuclear and particles
…n of the radius and exponential nature of decay for nuclei as well as quantum physics: the photoelectric effect and photons, wave particle duality and atomic models. Key questions What was Rutherford's experiment and what did he discover? Nuclei…
Atomic, nuclear and particles
Atomic models
…ist in discrete locations. Essentials Electrons and quantum Quantum physics So far we have considered light to behave as a wave. However, light also behaves as discrete quantised particles (photons) in certain experiments. Energy and wavelengths of…
Atomic, nuclear and particles
Structure of matter
…epts Photons and virtual photons Photons are the exchange particles associated with the electromagnetic force. A photon is a wave packet that carries an energy that is proportional to its frequency: \(E=hf\) Virtual photons only exist between particl…
Electricity and magnetism
…f a diode in the series circuit. All current in the forward direction is transmitted; no current flows in reverse bias. Full wave rectification uses two diode pathways (in opposite directions) to enable the current to flow at all times. Each diode pa…
Revision tips
Misconceptions
…weight Molecules in a liquid are not always further apart than those in a solid Air molecules do not vibrate when a sound wave passes The normal force acts perpendicular to the surface…
Electricity and magnetism
Capacitors
…acitance. Summary Rectification Capacitors can be used in rectification to overcome the sinusoidal limitation of full wave diode rectification. The presence of a capacitor in parallel with the load smooths the current through the resistor by c…
Electricity and magnetism
Faraday's law
…to a magnetic field (or vice versa): Fossil fuel power stations Nuclear power stations Wind turbines Hydroelectric turbines Wave and tidal turbines Geothermal Check out Energy sources if you need a recap! Other uses The following devices use electro…
Exam questions
SL practice paper 2
…ncy and amplitude Travelling in opposite directions Interfere with each other The most regular occurence of this is a single wave reflecting back onto itself. Node: Point that has zero amplitude Wavelength (λ): The distance between two equivalent poi…
Thermal
Thermal concepts
…about as a whole (rather than individual particles). Radiation is the transfer of heat by all hot objects by electromagnetic waves (infra red). Radiation can travel through any substance or vacuum. Black objects both radiate and absorb better than li…
Options
AHL Further cosmology
…models of the universe. Fluctuations in the CMB While StudyIB Physics geeks will know that we prefer to show the cosmic microwave background as being homogeneous and isotropic, students at AHL must also be prepared to discuss the observed anisotropie…
Atomic, nuclear and particles
Rutherford model
…mple of a scientific discovery where the theory developed from an experiment. Scattering Analysing the path of particles (or waves) bouncing off an object is a common way to find out what that object is. Ask a friend to place blob(s) of plasticine u…
Electricity and magnetism
Magnetic fields
…f rotation not acceleration? What is the connection between magnetic fields and electric current? And why don't magnetic waves exist without electric waves? Key Concepts Magnets Iron is the most common magnetic material. This means that it cont…
Atomic, nuclear and particles
Electron energy levels
…evels is quantized. The similarity between this and the harmonics in a pipe led to the the realisation that particles have wavelike properties (and vice versa). Electrons can be diffracted! Key Concepts Electrons in an electric field The path of el…
Energy production
Energy to the Earth
…fferently with electromagnetic radiation. The greenhouse effect Radiation entering the Earth's atmosphere increases in wavelength (tending towards infrared) when it reflects off the Earth's surface. Greenhouse gases absorb this infrared rad…
Energy production
…the solar constant. Find out more. What is the greenhouse effect? Radiation entering the Earth's atmosphere increases in wavelength (tending towards infrared) when it reflects off the Earth's surface. Greenhouse gases absorb this infrared rad…
Start here
Coming soon
…as a textbook (and is cheaper than an hour's tuition!). Latest updates: Past paper walk-throughs are up and running AHL Waves and EM Induction topics AHL Fields and Quantum topics Two Options in full Things to look out for... Required practical…
Energy production
Global thermal energy transfer
…oncluding topic is a bit of everything and is a great check of so much that you have already studied: conservation of energy waves electromagnetic spectrum nuclear fusion electron energy levels This page is a quick summary, but for fuller details, go…
Revision tips
Mind maps and revision techniques
…nus Engineering) Thermal - Bitesize Gallery: Thermal - bitesize Mode: simple Thumb width: 128px Layout: row Oscillations & waves - Most (all but Standing Waves) Oscillations & waves - Bitesize Gallery: Waves - bitesize Mode: simple Thumb width: 12…
Energy production
Energy from the Sun
…at a full emission spectrum is released. We can visualise this spectrum on a graph of power (or intensity or energy) against wavelength. The hotter the object, the more power will be produced and the shorter the peak wavelength will be. The sun is a…
Twitter 
Facebook 
LinkedIn