Waves Flashcards
Definition of wave
A wave is something which transfers energy (and information) without transferring matter
What is a transverse wave?
A transverse wave is one where the vibration is perpendicular to the direction of energy transfer
What is the wavelength
The distance between two consecutive crests
What is the amplitude
The height between the equilibrium position and the crest
What happens in a transverse wave when the wave is transmitted through the medium
Particles move up and down
Examples of transverse waves
Water
Light
Electromagnetic
What is a longitudinal wave
A longitudinal wave is one where the direction of vibration is along the same line as the direction of energy transfer
What is a compression
A region of high pressure due to particles being close together
What is a rarefaction
A region of low pressure due to particles being spread further apart
What is frequency
The number of complete cycles/oscillations/vibrations per second
What is frequency measured in
Hertz
What is time period
The time taken for one complete cycle - in seconds
T=1/T
F=1/T
What is the wave equation?!!!!!
Speed = frequency x wavelength
GPE equation
GPE = mass x gravitational field strength x height
KE equation
1/2 x mass x (speed)^2
M = 2KE/V^2
What happens when an object falls
It loses GPE and gains an equal amount of KE
Work and power
Energy changed = work done
Power is the ….
Rate of energy transfer (work transfer)
Power equation
Power = work done/time taken
What is the Doppler effect
The apparent change in frequency of a wave when there is a relative motion between the source and the observer
When is the Doppler effect noticeable
In sound (change of pitch) In light (change in colour)
It’s only noticeable when the speed of movement gets around the speed of the wave
