P12: Waves

Question 1

What are examples of transverse wave?

Answer 1

Ripples on water, electromagnetic and waves of strings

Question 2

What are examples of longitudinal waves?

Answer 2

Sound and p-waves

Question 3

What is the amplitude?

Answer 3

The maximum displacement of a point on a wave away from its undisturbed position

Question 4

What is the wavelength?

Answer 4

The distance from a point on one wave to the equivalent point on the adjacent wave

Question 5

What is the frequency?

Answer 5

The number of waves passing a point each second

Question 6

What is the wave speed? What is the formula?

Answer 6

The speed at which the wave transfers energy through the medium. Wave speed = frequency x wavelength

Question 7

What is the range of normal human hearing?

Answer 7

20Hz to 20KHz

Question 8

What DON’T waves transfer?

Answer 8

Matter

Question 9

What is the formula for wave frequency?

Answer 9

Number of oscillations / time

Question 10

What is true about a particle in a wave?

Answer 10

It will always return to its rest position

Question 11

What is a transverse wave?

Answer 11

A wave which has oscillations perpendicular to the direction in which the waves transfer energy

Question 12

What is a longitudinal wave?

Answer 12

A wave which has oscillations parallel to the direction in which the waves transfer energy

Question 13

Describe evidence that a wave moves and not the substance (e.g. water)

Answer 13

When an object is dropped on water, the waves spread out and travel across the surface

Question 14

Describe evidence that a sound wave moves and not the air

Answer 14

The sound waves travel through the air in a tuning fork, but the air doesn’t travel away from the vibrating object as it would cause a vacuum

Question 15

What is the relationship between amplitude and the energy a wave carries?

Answer 15

The bigger the amplitude, the more energy the wave carries

Question 16

Describe a method to measure the speed of sound in air

Answer 16

Two people should stand apart, and one of them should bang 2 cymbals together. The crashing sound will delay as sound travels slower than light. Use a stopwatch to time the interval between seeing and hearing. Repeat several times and calculate mean. Use speed = distance/time

Question 17

What do the parallel lines on a ripple tank represent?

Answer 17

The peak of a wave

Question 18

What changes and stays the same when waves travel from one medium to another?

Answer 18

Wavelength and speed changes but frequency stays the same

Question 19

Why does frequency remain constant when waves travel from one medium to another?

Answer 19

Because the source is producing the same number of oscillations per second

Question 20

What is the effect of sound waves on the ear drum?

Answer 20

Sound waves enter the ear and cause the ear drums to vibrate, sending signals to the brain about what is being heard.

Question 21

What are 2 uses of ultrasound?

Answer 21

Foetus scanning and dog whistles

Question 22

In what state of matter is the speed of sound highest and why?

Answer 22

Solids because they are more rigid and hard to compress

Question 23

What seismic wave is longitudinal?

Answer 23

P-waves

Question 24

What seismic wave cannot travel through liquids?

Answer 24

S-waves

Question 25

What property of water can be found using ultrasound?

Answer 25

Depth

Question 26

What does the do to seismic waves?

Answer 26

Causes the rarefaction of them

Question 27

What is the easiest way to record wavelength, frequency and speed of a wave in a ripple tank?

Answer 27

Record on the phone to play at different speeds and freeze image

Question 28

What does wavespeed depend on in the ‘waves in a solid’ practical?

Answer 28

The tautness of the string and the mass

Question 29

What determines whether a wave is absorbed, transmitted or reflected?

Answer 29

The wavelength and property of material

Question 30

What happens to the refracted ray when moving from a less dense material to more dense?

Answer 30

Moves towards the normal and slows down

Question 31

What happens to the refracted ray when moving from a less dense material to more dense?

Answer 31

Moves towards the normal and slows down

Question 32

What seismic wave is faster?

Answer 32

P-waves