P5.1

Question 1

What is a wave?

Answer 1

A regular disturbance that transfers energy in the direction the wave is travelling without transferring matter.

Question 2

What are the two types of waves?

Answer 2

1. Transverse
2. Longitudinal

Question 3

What is a transverse wave?

Answer 3

A wave for which the oscillations are perpendicular to the direction of energy transfer.

Question 4

What is a longitudinal wave?

Answer 4

A wave for which the oscillations are parallel to the direction of energy transfer.

Question 5

Give two examples of transverse waves.

Answer 5

Electromagnetic waves
Seismic s-waves

Question 6

Give two examples of longitudinal waves

Answer 6

Sound waves
Seismic p-waves

Question 7

What are the two parts of a longitudinal wave called?

Answer 7

Compressions and rarefactions

Question 8

What is a wave’s amplitude?

Answer 8

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

Question 9

What is wavelength?

Answer 9

The distance from a point on a wave to the same position on the adjacent wave. Most commonly peak to peak or trough to trough.

Question 10

What is the frequency of a wave?

Answer 10

The number of waves that pass a given point each second.

Question 11

What is the unit used for frequency?

Answer 11

Hertz, Hz

Question 12

What is meant by a frequency of 200Hz?

Answer 12

200 waves pass a given point each second

Question 13

What is wave speed?

Answer 13

The speed at which energy is transferred through a medium.

Question 14

What does a wave transfer?

Answer 14

Energy

Question 15

State the equation used to calculate wave speed. Give appropriate units.

Answer 15

Wave speed= Frequency x Wavelength.

Speed (m/s), Frequency (Hz), Wavelength (m)

Question 16

What word is used to describe when a wave bounces off a surface?

Answer 16

Reflection

Question 17

What is refraction?

Answer 17

Refraction is the change in speed of a wave as it reaches a boundary between two media, resulting in a change in direction.

Question 18

What property of wave is not changed by refraction?

Answer 18

The frequency.

Question 19

When entering a denser material, light waves…

Answer 19

… slow down and bend towards the normal.

Question 20

What is a ripple tank?

Answer 20

A shallow glass tank with an oscillating paddle/needle to create waves. It is illuminated from above so the waves can be seen on the surface below the tank.

Question 21

Describe how to demonstrate reflection using a ripple tank.

Answer 21

Waves will reflect off the glass sides of the tank.

Question 22

How do sound waves travel through a solid?

Answer 22

The particles in the solid vibrate and transfer kinetic energy through the material.

Question 23

How does the human ear work?

Answer 23

1. The outer ear collects the sound which travels into the ear.
2. The sound waves cause the eardrum to vibrate at the same frequency.
3. This is amplified by three ossicles (small bones)
4. This causes the hair in the cochlea to vibrate.
5. The cochlea converts the vibrations into electrical signals.
6. The signals are passed to brain through the auditory nerve.
7. The brain converts the electrical signals into sound.

Question 24

What is the frequency range of human hearing?

Answer 24

20 Hz - 20kHz

(1kHz = 1000 Hz)

Question 25

What are ultrasound waves?

Answer 25

Waves which have a frequency higher than the upper limit of human hearing.

Question 26

Give an example use for ultrasound waves.

Answer 26

Medical or industrial imaging.