P9: Sound and Ultrasound

Question 1

Can sound waves travel through a vacuum?

Answer 1

They are mechanical: no.

Question 2

What speed does sound travel at?

Answer 2

340m/s

Question 3

What is a humans frequency range?

Answer 3

20 - 20 000 Hz

Question 4

Echoes

Answer 4

Sound waves reflected from a smooth, hard surface.

Question 5

Loud and High Pitched

Answer 5

Question 6

Loud and Low Pitched.

Answer 6

Question 7

Increasing the loudness of a sound…

Answer 7

… Increases its amplitude.

Question 8

Increasing the frequency of a sound…

Answer 8

…Increases its pitch.

Question 9

Ultrasound Waves

Answer 9

A sound wave undetectable to the human ear (too high)

Question 10

Positives of ultrasound

Answer 10

Non-ionising

Produces images of organ tissues as well as bones.

Question 11

How does an ultrasound transducer work?

Answer 11

The waves it emits are partially reflected by different tissue boundaries in its path.

These return to the transducer as a sequence of pulses that build up an image of the internal body.

Question 12

Distance travelled by an ultrasound pulse =

Answer 12

speed of ultrasound waves in body tissue x time taken.

Question 14

Answer 14

Loud and High Pitched

Question 15

Answer 15

Loud and Low Pitched.