Waves

Question 1

What is frequency?

Answer 1

The number of waves passing a point each second

Question 2

What is wavelength?

Answer 2

The distance between a point on one wave and the same point on the next wave

Question 3

What is amplitude?

Answer 3

The distance between the top and bottom of the wave divided by 2 (the distance between the middle and top of the wave)

Question 4

What is period?

Answer 4

1/frequency

Question 5

What is wave speed?

Answer 5

The speed of a wave (measured in m/s)

Question 6

What are longitudinal waves?

Answer 6

Waves where the particles in the material the wave is travelling through move back and forth along the same direction that the wave is travelling

Question 7

What are transverse waves?

Answer 7

Waves where the particles in the material that the wave is travelling through move at right angles to the direction that the wave is travelling through

Question 8

Give a few examples of longitudinal waves

Answer 8

• Sound waves

- Seismic P waves

Question 9

Give a few examples of transverse waves

Answer 9

• Light waves
• Water waves
• Seismic S waves

Question 10

What 4 things can happen when a wave reaches a boundary?

Answer 10

It can either be refracted, reflected, absorbed or transmitted

Question 11

What is a crest?

Answer 11

The top of a wave

Question 12

What is a trough?

Answer 12

The bottom of a wave

Question 13

What is transmission?

Answer 13

When a wave is transmitted/passes through a material

Question 14

What is absorption?

Answer 14

When a wave is absorbed by a material

Question 15

What is reflection?

Answer 15

When a wave is reflected back the way it came by a material

Question 16

What is refraction?

Answer 16

When a wave changes speed and direction when it passes through a material

Question 17

When are sound waves produced?

Answer 17

When objects vibrate

Question 18

How are sound waves produced from a drum?

Answer 18

The drum is hit and the skin begins to vibrate and particles of air are compressed together. The drum skin then bounces back and the compressed particles move inwards. This causes a sound wave to move outwards from the drum

Question 19

How does the ear detect sound?

Answer 19

Sound waves are channelled down the ear canal and cause the ear drum to vibrate. These vibrations pass through the ear further and are converted into electrical signals and carried to the brain

Question 20

Why can the ear only hear sounds in the range 20Hz- 20,000Hz?

Answer 20

The conversion of sound waves to vibrations only works in a limited frequency range

Question 21

What is infrasound?

Answer 21

Sound waves that have a frequency below 20Hz. Travel through the earth as shockwaves from tsunamis, earthquakes or volcanoes

Question 22

What is ultrasound?

Answer 22

Sound waves with a frequency above 20,000Hz. Used in pre-natal scans to make images of the inside of the body

Question 23

What is sonar?

Answer 23

Equipment used to find the depth of water beneath objects using pulses of ultrasound

Question 24

What does the speed of sound in a material depend on?

Answer 24

The density of the material

Question 25

What is dispersion?

Answer 25

When light separates out into the different colours making it up due to their different frequencies