Waves

Question 1

What are the two types of wave

Answer 1

longitudinal, transverse

Question 2

What is the amplitude of a wave

Answer 2

height of the wave measured from the centre of the wave.

this is a measure of the energy carried by the wave

Question 3

What is the wavelength

Answer 3

this is the distance between two corresponding points on the wave and it measured in metres

Question 4

WHat is the symbol for wavelength

Answer 4

lambda λ

Question 5

What is the frequency

Answer 5

this is how many waves pass by every second

Question 6

What is frequency measured in

Answer 6

Hertz (Hz)

Question 7

What is the time period

Answer 7

this is the time it takes for one wave to complete its cycle(s)

Question 8

What does a high frequency mean in terms of time period

Answer 8

short time period

Question 9

What does a low frequency mean in terms of time period

Answer 9

longer time period

Question 10

what is the equation for time period of a wave

Answer 10

T = 1/f

Question 11

What is the equation for frequency of a wave

Answer 11

f = 1/T

Question 12

What is a transverse wave

Answer 12

A wave that oscillates particles perpendicular to the motion of the wave

Question 13

What is a longitudinal wave

Answer 13

Particles vibrate in the same direction as the motion of the wave

Question 14

WHat is the length of a wave either from peak to peak or trough to trough

Answer 14

wavelength

Question 15

What is the equation for wave speed

Answer 15

frequency x wavelength (v= fλ)

Question 16

WHat is wave speed measured in

Answer 16

m/s

Question 17

What is the law of reflection

Answer 17

The angle of incidence, i equals the angle of reflection, r

Question 18

Name 2 longitudinal waves

Answer 18

-sound waves
-seismic waves
-ultrasound waves

Question 19

Name 3 transverse waves

Answer 19

-All EM waves
-Water waves
-Wave on a string

Question 20

What do you use an oscilloscope for

Answer 20

measuring the speed of a wave

Question 21

How do you use an oscilloscope

Answer 21

-Set up oscilloscope so the detected waves at each microphone are shown as separate waves
-Start with both microscopes next to the speaker, then move one away until the two waves are aligned on the the display but have moved exactly one wavelength apart
-Measure the distance between the microphones to find one wavelength
-Use V=fλ to find the speed (v) of the sound waves passing through the air- the frequency is whatever you set the signal generator to.
-The speed of sound in air is around 330m/s so check your results agree with this

Question 22

How to measure the speed of water ripples using a lamp

Answer 22

-use signal generator attached to dipper of a ripple tank; use to create waves at a set frequency
-use a lamp to see wave crests on a screen below the tank, make sure size of shadows equal size of waves
-distance between each shadow line is equal to one wavelength. Measure the distance between the shadow line is equal to one wavelength.
-Measure the distance between shadow lines 10 wavelengths apart, divide this by 10 to find average.
-use v=fλ to find speed
-suitable for investigating waves because you can measure wavelength without disturbing the wavelength

Question 23

WHy are wave tanks useful for investigating waves

Answer 23

You can measure the wavelength without disturbing the waves

Question 24

True or false. All waves can be absorbed, transmitted, or reflected

Answer 24

True

Question 25

What is a specular reflection

Answer 25

When a wave is reflected in a single direction by a smooth surface
e.g. light reflected by a mirror

Question 26

What is a diffuse reflection

Answer 26

When a wave is reflected by a rough surface and the reflected rays are scattered in lots of different directions
e.g. piece of paper

Question 27

What does a surface look like when light is reflected by a rough surface and you don’t get a clear reflection of objects

Answer 27

matte