Atomic, nuclear and particles
Photoelectric effect and photons
The photoelectric effect is indisputable evidence for the particle nature of light. Particles of light are discrete and named photons. The energy of a photon depends not on intensity but frequency. Key Concepts Photoelectric effect There is a signifi…
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…
Atomic, nuclear and particles
Wave particle duality
The evidence from the photoelectric effect, Compton 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 Electro…
Oscillations and waves
AHL Waves
…gle slit? What affects the interference patterns for two or more slits? What is thin film interference? Key Concepts Doppler effect The Doppler effect is the change in frequency in observed sound due to relative motion between source and observer. F…
Oscillations and waves
Multiple slit interference
We now understand the diffraction effect of a single slit on light passing through. But what about two slits? When light passes through two or more slits, it interferes. A pattern can be observed if the waves are coherent. The effect continues with m…
Oscillations and waves
Phase
A juggler may not understand the mathematical representation of phase, but they are using the effect as they throw balls in the air at different times. It is important to understand the concept of phase before starting the Waves section. In short: a…
Electricity and magnetism
Force on a current-carrying conductor
…n a complete circuit) experiences a force when placed in a magnetic field due to its own magnetism. This is called the motor effect. We use Fleming's left hand rule to find out the correct direction of force. Key Concepts Fleming's left hand…
Electricity and magnetism
…agnetic domains or moving charges. After studying this topic, you should be able to: State what an electric field is and its effect on charges Discuss what affects the size of an electric force Suggest uses for charges moving around a circuit Define…
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AHL Damped and driven oscillations
…le harmonic motion topic we considered natural oscillations of pendula and masses on springs. But so far we have ignored the effect of the fluid in which the oscillations are taking place and therefore the effects of damping. And what if these oscill…
Energy production
Energy to the Earth
…re The atmosphere is made of many different gases that interact differently with electromagnetic radiation. The greenhouse effect Radiation entering the Earth's atmosphere increases in wavelength (tending towards infrared) when it reflects off…
Energy production
Global thermal energy transfer
…re-radiated in all directions. Some of the radiation goes back to the Earth causing the temperature to rise: the greenhouse effect. Test Yourself Use flashcards to practise your recall. Flashcards Topics: Global energy transfer Levels: All Number…
Atomic, nuclear and particles
AHL Quantum
…etic radiation, the wavelengths of electrons and the energy levels of an atom. Key Concepts Photon interactions with matter Photoelectric effect The photoelectric effect provides evidence for the quantum nature of light. Individual photons of light…
Atomic, nuclear and particles
…content includes the determination 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…
Energy production
Renewable sources I
…cell is made of a sandwich of two types of semiconductor material. Sunlight excites electrons in the upper layer due to the photoelectric effect. This movement of electrons is an electric current. A solar power station reflects sunlight onto a furna…
Start here
Investigation ideas
…tial close to a sphere Charge distribution Van de graaf generator Action of points Optimum operating conditions Spark length Effect of humidity Electric force Radial field Basic coil set Self inductance Flux density Falling magnet Mutual inductance E…
Oscillations and waves
…irection of displacement is parallel to the direction of propagation. Find out more. What is the Doppler effect? The Doppler effect is the change in frequency in observed sound due to relative motion between source and observer. Find out more. What i…
Energy production
…blades. When a conductor (such as a wire) moves in a magnetic (B) field, the electrons in it experience a force. The overall effect of this is an electro-motive force (ϵϵ), which is a potential difference converting an energy source in to electrical…
Electricity and magnetism
Capacitors
…ential difference across it. The current falls. Exponential relationships The repelling nature of the charges stored has the effect that the rate of discharge from a capacitor is proportional to the charge remaining on a capacitor. Mathematically, \(…
Basics
Error and uncertainty
…cepts Errors when measuring A systematic error causes all measurements to be offset by exactly the same amount. This has the effect of changing the y-axis on a linear graph, for example: a non-zeroed ruler when measuring length failing to subtract th…
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Angular momentum and rotational kinetic energy
…rads-1) Angular momentum is a conserved quantity: total angular momentum remains constant. Ice skaters make good use of this effect when spinning. With limbs spread out, the moment of inertia is high as more mass is at a distance from the pivot. This…
IA 2022
…affect the vertical distance travelled by the ball due to the ruler coming back to its original position? Hamza: What is the effect of changing the liquid's height in the container on the range of the fluid exiting the container through a tiny orific…
Electricity and magnetism
Electric circuits
…of the battery from the maximum possible EMF. It is represented as a small resistor placed next to the cell and has the same effect as a resistor placed anywhere else. Terminal potential difference: The actual potential difference across the terminal…
Atomic, nuclear and particles
Nuclear physics
…). Their relatively large mass and charge mean that they are the most ionising type of radiation. However, this also has the effect that they can only penetrate 2-3 cm of air and they are absorbed fully by a sheet of paper. Alpha decay example: From…
Exam questions
HL practice paper 2
…in distance. The central maximum is most intense. The two-slit interference pattern is modulated by the one-slit diffraction effect. This affects the distribution of intensity against distance on the screen from the centre by capping the double slit…
Basics
Linear graphs
…Law. Tutorial This video shows the effects of changing \(m\) and \(c\) on the appearance of the line. Summary Predict the effect of moving the sliders. Test Yourself Use quizzes to practise application of theory. Linear 20/03/2016 [SLIDES]: mult…
Mechanics
Inertia, momentum and impulse
…ntum (p) = mass (m) x velocity (v) The unit of momentum is a combination of what it is calculated from, usually kg m s-1 The effect that a ball has when it hits a wall depends on its momentum. Impulse Impulse is the change of momentum (and, consequ…
Circular motion and gravity
Circular motion
…we might refer to a 'centrifugal force' as flinging objects outward. In fact, this does not exist and instead is an effect of the absence of sufficient force while the system turns the corner. Relative motion does not always require a force…
Oscillations and waves
Oscillations
…me period of a pendulum, L is the length of the string in m g is gravitational field strength NB: The mass of the bob has no effect on time period, nor does amplitude! Time period of a mass on a spring, m is the mass in kg k is the spring constant i…
Electricity and magnetism
Magnetic fields
…ting magnetic field will experience a force due to the interactions of the magnetic fields. This is often known as the motor effect. If the field is perpendicular to the current the the force is perpendicular to both. Fleming's left hand rule ca…
Atomic, nuclear and particles
Particle interactions
…rticles. Essentials Feynman diagrams Look out for the rules described on the Structure of matter page. First, notice the effect of rotating the lines. Complex interactions Now look for the effects of these subtle variations in the lines for a m…
Circular motion and gravity
…ay speech, we might refer to a centrifugal force as flinging objects outward. In fact, this does not exist and instead is an effect of the absence of sufficient force while the system turns the corner. Find out more. What does Newton's law of gra…
Energy production
Power stations
…vement. When a conductor (such as a wire) moves in a magnetic (B) field, the electrons in it experience a force. The overall effect of this is an electro-motive force (\(\epsilon\)), which is a potential difference converting an energy source in to e…
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Torque and moment of inertia
…e the torque on the body. In this case, the total torque acting is: \(\Gamma=Fr\sin 90+Fr\sin 90\) \(\Gamma=2Fr\) Watch the effect of a couple on a rod. Essentials Moment of inertia is the rotational equivalent of mass. The moment of inertia of a…
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Rotational dynamics
…ination of the situation below reveals that \(\alpha={Mgr\over Mr^2}={g\over r}\), so only the perpendicular distance has an effect. A graph of torque vs time would be proportional in shape to the equivalent angular acceleration graph. Test Yourse…
Oscillations and waves
Thin film interference
…iation in the thickness of a film will result in the appearance of bands of colour from an original white light source. This effect can be used to test the flatness of manufactured glass surfaces. Test Yourself Use quizzes to practise application o…
Energy production
Energy from the Sun
…y curve. This is intuitive, as shorter wavelengths correspond with higher freqencies and energies. However, it does have the effect that the very hottest stars in terms of temperature actually release much more gamma and X-ray radiation than infrared…
Why two lamps don't interfere
…r of atomic wave sources that have random phase, the wavefront produced from each lamp changes with time so any interference effect will not be stable. To achieve interference the light from one lamp can be passed first through one slit then two slit…
Electricity and magnetism
AC generators
…verage power (W) All of these equations are found in the data booklet and can be used to solve problems for an AC circuit. Effect of changing frequency From the equation it is easily to identify that increasing magnetic flux density, the area of th…
Electricity and magnetism
Faraday's law
In the SL Magentism course, you will have studied the motor effect, in which a current-carrying conductor or moving charge experiences a force in a magnetic field. In the HL course, we move to electromagnetic induction. When a magnetic field is chang…
Electricity and magnetism
AHL EM induction
…the load resistor at the same side. The addition of a capacitor to a diode bridge rectification circuit creates a smoothing effect. Diodes are made from semiconducting materials containing a p-n junction. Capacitors Capacitance The capacitance of…
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