Topic 4

Question 1

What kind of waves are sound waves

Answer 1

Longitudinal waves

Question 2

How is sound produced

Answer 2

By vibration of particles in a medium

The vibrations mean that sound waves travel in a series of compressions and rarefactions

Question 3

What frequency of sound waves can our ears here

Answer 3

Between 20Hz and 20,000Hz

Question 4

What are sound waves with frequencies above 20,000Hz called

Answer 4

Ultrasound

Question 5

What are sound waves with frequencies below 20Hz called

Answer 5

Infrasound

Question 6

What is a use of ultrasound

Answer 6

Used by doctors to Pedro, scans of a developing foetus

Question 7

Why is sonar ultrasound used

Answer 7

The waves can penetrate water to long distances due to their high frequency (greater than 20,000Hz)

Question 8

Describe the process which convert wave disturbances between sound waves and vibrations in solid

Answer 8

Sound waves can travel through solids causing vibrations in the solid
In the ear sound waves cause the ear drum and other parts to vibrate which causes sensation of sound. The conversion only works over a limited frequency range which is 20-20,000Hz

Question 9

What happens if the medium of the sound wave is rigid

Answer 9

the higher the speed of the sound wave through the medium.