A transverse wave is a wave for which the oscillations are perpendicular to the direction of energy transfer
A longitudinal wave is a wave for which the oscillations are parallel to the direction of energy transfer
Two types of waves are Transverse and Longitudinal
Examples of longitudinal waves
Sound waves
Seismic p-waves
Parts of a longitudinal wave
Compressions
Rarefactions
Frequency of a wave
The number of complete wavelengths that pass a point in a given time
Wavelength
The distance from a point on a wave to the same position on the adjacent wave. Most commonly peak to peak or trough to trough
Wave's amplitude
The maximum displacement of a point on a wave from its undisturbed position
Frequency of 200Hz means 200 waves pass a given point each second
Point on a wave to the same position on the adjacent wave
Frequency of a wave
The number of waves that pass a given point each second
Wave speed is the speed at which the wave moves or at which energy is transferred through a medium
Equation used to calculate wave speed: Wave Speed = Frequency x Wavelength. Units: Speed (m/s), Frequency (Hz), Wavelength (m)
Word used to describe when a wave bounces off a surface is Reflection
Wave transfers energy
How sound waves travel through a solid: The particles in the solid vibrate and transfer kinetic energy through the material
Frequency range of human hearing is 20 Hz - 20kHz
Ultrasound waves have a frequency higher than the upper limit of human hearing (20kHz)
Seismic waves are produced by earthquakes and produce both P-waves and S-waves
Difference between P-waves and S-waves: P-waves travel through both solids and liquids, while S-waves only travel through solids (not liquids)
Technique used to detect objects in deep water and measure water depth is echo sounding. High frequency sound waves are emitted, reflected, and detected. The time difference between emission and detection, alongside wave speed, is used to calculate distances
Electromagnetic waves all travel at the same speed in a vacuum and in air
Order the types of electromagnetic radiation from lowest to highest frequency
1. Radio waves
2. Microwaves
3. Infrared
4. Visible Light
5. Ultraviolet
6. X-rays
7. Gamma Rays
When radio waves are absorbed, they can induce oscillations in a circuit with the same frequency as the waves themselves
Property causing refraction in different mediums
Velocity
Wave speed is slower in denser materials, causing refraction
Direction of waves when entering a denser medium
They bend towards the normal
The angle of refraction is less than the angle of incidence
Radio waves can be produced by oscillations in an electrical circuit
Electromagnetic waves form a continuous spectrum
Gamma rays originate from changes in the nuclei of atoms
Ultraviolet waves can cause the skin to age prematurely and increase the risk of developing skin cancer
Oscillations in a circuit have the same frequency as the waves themselves
rays and Gamma rays, being ionising radiation, can cause mutations in genes and lead to an increased risk of developing various cancers
A convex lens forms an image by refracting parallel rays of light and bringing them together at a point known as the principal focus
Practical uses for radio waves
Television transmission
Radio transmission
Practical uses for infrared radiation
Electrical heaters
Cooking food
Infrared cameras
Practical uses for microwave radiation
Satellite communications
Cooking food
The focal length of a lens is the distance from the lens to the principal focus
Refraction is the wave phenomenon used by lenses to form an image