Waves
The amount the mass moves up and down is called the amplitude of oscillation. This is half of the value from trough to crest.
The rate at which the mass moves through its oscillation is referred to as frequency. Faster oscillation = higher frequency. It is measured in Hertz (Hz) which is 1/s
Waves such as sound and light have velocity (m/s) which refers to how quickly it moves or propagates through space.
The duration of the oscillation is known as the period given symbol (T) and is measured in units of time, usually second.
The distance of the wave and where it travels is known as the wavelength
For the wavelength, this will be the distance between a peak and a peak (as it is the horizontal distance covered by each cycle). If given distance from peak to trough, double this to "reach the next peak" and a full cycle.
For a given wave, its velocity will be determined by its frequency (how many times it oscillates per second) multiplied by its wavelength (how far it moves for each oscillation). This relationship gives us what is known as the wave equation. v = f * landa symbol
In general, the frequency of a wave will not change as it moves through space (including between different mediums), while velocity and wavelength will change.
Light
Light is an example of an electromagnetic wave (alongside microwaves, x-rays, radio waves)
This means that the oscillations are simultaneous fluctuations in both an electric field and a perpendicular magnetic field.
Sound
Sound is due to the physical interactions between particles colliding and vibrating into one another, caused by fluctuations in pressure
You can imagine this as being akin to cars on a highway reaching a traffic jam. They are initially quite spaced out, but then compress closer to one another, before spacing back out again.
Longitudinal wave meaning that the oscillations take place in the same direction as the movement of the wave.
This causes particles to become compressed (more particles closer to each other) and then spread further apart which are called rarefactions.
Transverse waves meaning that oscillations (in electrical and magnetic fields) take place perpendicular to the direction of the wave's travel.
Sounds have a set velocity for a particular medium. Speed of sound
In air this is 343 m/s
Will vary depending on medium. Solids and liquids have higher velocities compared to gases, due to the molecules being more closely packed together in liquids and solids.
Volume is described as intensity and loudness.
Intensity is an absolute measurement, measured on its own and quantified without needing to be compared to any other measurement. It is defined as the amount of power (Watts) per square meter W/m^2
Loudness is measured in decibels (dB) is a description of how loud a sound is and as such must be compared with another sound.
We can observe, measure and analyse electromagnetic radiation (light) through photons to carry this force/energy.
Photons are an elementary particle that can only be created or destroyed (not transferred). They are massless that move as transverse waves at the speed of light 3 x 10^8**
They are particles AND waves
Optics
Study of the behaviour and properties of light
When looking at light in terms of ‘rays’, it travels in a straight line and is often affected by reflection and refraction when entering a different medium
The law of reflection demonstrates that the angle of reflection equals the angle of incidence, or angle of incoming light
The law of refraction states that the sine of the angle of incidence divided by the sin of the angle of refraction (which is dependant on incoming media) is constant.
Diffraction
When light travels through a slit or encounters an object, it can experience a ripple process called diffraction which allows the light to bend in a certain direction that is dependent upon the difference between its wavelength and the size of the slit of object.
This phenomena can also explain why we can hear sound or people talking when we are around the corner. Like light, sound can also bend and diffract due to its wave-like properties.
Photons = light
Vibrations = sound