Waves - General
What is a wave?
A method of energy transfer from one place to another
In a transverse wave, which direction to the vibrations move compared to the wave?
Perpendicular (right angles)
what direction do particles vibrate in longitudinal waves?
parallel
what is the formula linking speed, distance, and time?
speed = distance / time
what is reflection?
bouncing of waves
Do waves transfer energy or matter?
Energy only
Name one type of transverse wave
light / water / electromagnetic (radio, xray, gamma etc) / S waves
name a longitudinal wave
sound wave / p wave / pressure wave
what is the wave equation?
wave speed = frequency x wavelength
what is refraction?
change in the direction of a wave due to the speed of the wave decreasing / increasing
What is the name of the highest and the lowest point on a wave?
Peak/ Crest and trough
... did you do it?
what is the difference between a compression and a rarefaction?
compression = close particles
rarefaction = spread out
a wave has a wavelength of 4m and a frequency of 3Hz, what is the speed of the wave?
4m x 3Hz = 12m/s
when light enters glass from air, what happens to its speed (And why?)
it slows down, because glass is more dense
Complete the sentences:
Transverse waves vibrate ________________ to the movement of energy.
Longitudinal waves vibrate ________________ to the movement of energy.
Perpendicular & Parallel
A student increases the amplitude of a light wave, what happens to the brightness?
It gets brighter because amplitude is an increase in energy
do the longitudinal wave dance
... did you?
rearrange v = fλ to find frequency
f = v / λ
explain why a straw looks bent in water
refraction - light changes speed and direction
Give one example of a wave that needs a medium to travel through and one that doesnt.
What is a medium.
Sound, needs a medium
Light, does not
Medium = a substance which waves travel through
If you increase the frequency of a light wave, what happens to the wavelength and the wave speed?
the wavelength gets smaller, as the speed stays the same
why can sound not travel through space?
there is no medium in space, space is a vacuum
a student doubles the frequency of a wave, bug keeps the speed the same. What happens to the wavelength - be specific
the wavelength must halve if the frequency doubles because v = fλ