P6. Waves & Sounds

Question 1

Wave

Answer 1

A transfer of energy from one point to another without transferring matter

Question 2

Transverse waves

Answer 2

Waves in which the direction of vibration of the particles in the medium is perpendicular to the direction of propagation of the wave

Question 3

Longitudinal waves

Answer 3

Waves in which the direction of vibration of the particles in the medium is parallel to the direction of propagation of the wave

Question 4

Frequency

Answer 4

Number of oscillations per second

Question 5

Period

Answer 5

Time taken for 1 oscillation

Question 6

Wavelength

Answer 6

The distance between successive crests of a wave

Question 7

Amplitude

Answer 7

The maximum distance a point moves from its rest position when a wave passes

Question 8

Speed of sound

Answer 8

Solids: > 2000 m/s
Liquids: 1200 - 1900 m/s
Gases: approx. 330 m/s

Question 9

Uses of ultrasound

Answer 9

1. Cleaning machinery immersed in a tank of liquid
2. Breaking kidney stones and gall stones without patients needing surgery
3. Echo-sounding (to measure depth of water beneath ship)
4. Metal testing (to detect flaws in metals)
5. Scanning the womb (to scan and capture image of fetus in mother’s womb)