Studied by 2 people
Waves transfer…
Energy and information but not matter
Frequency
The number of complete cycles of the wave passing a point each second
Period
Amount of time it takes for one full cycle of a wave
Amplitude
Maximum displacement of a point on a wave from its rest position
Wavelength
Length of a full cycle of the wave
Period equation
1/frequency
In transverse waves…
Oscillations are perpendicular to the direction of wave travel
Transverse waves examples
Ripples in water, EM waves and seismic s-waves
In longitudinal waves…
Oscillations are parallel to the direction of wave travel
Types of longitudinal waves
Sound waves, seismic p waves
Wave speed equation one:
Speed= frequency x wavelength
Wave speed equation 2:
Speed= distance/time
When waves hit a boundary, they are…
Absorbed, transmitted or reflected
Absorbed
Energy is transferred to the materials energy stores
Transmitted
The wave continues travelling through the material leading to refraction
Reflected
The wave is bounced off the material
angle of incidence
the angle between the incident ray and the normal
angle of refraction
the angle between the refracted ray and the normal
angle of incidence=
angle of refraction
If the wave speeds up, the…
wavelength increases and it bends away from the normal
If the wave slows down…
The wavelength decreases and it bends towards the normal
Shorter wavelengths…
Bend more
Order of EM spectrum
Radio, micro, infrared, visible light, ultraviolet, x-rays and gamma rays
As you go along the line of the EM spectrum…
Frequency increases, wavelength decreases
Radio waves are used for
Broadcastings and communications
Microwaves are used for
Microwaves and communications
Visible light is used for
Photography and illumination
Infrared radiation is used for
Thermal imaging and TV remote controls
UV waves are used for
Sterilising water and detecting forged bank notes
X rays are used for
Looking inside objects and airport security scanners
Gamma rays are used for
Detecting and treating cancer, sterilising food
Danger of microwaves
Heats up cells in our body
Danger of infrared waves
Causes skin burns
Danger of ultraviolet waves
Damages eyes, causes skin cancer
Danger of x rays and gamma waves
Cause mutations which can lead to cancer
Why does light split into different colours when shined through a prism?
Different wavelengths travel at different speeds so refract by different amounts
Note 
Flashcard (28)