Sound waves and hearing

Question 1

What are sound waves?

Answer 1

Vibrations that pass through the molecules of a medium. As they are longitudinal, they travel in a series of compressions and rarefactions

Question 2

How do sound waves travel through a solid?

Answer 2

Causing particles inside the solid to vibrate which collide with neighboring particles ultimately passing on the vibrations. This passing of vibrations results in the transmission of the sound waves through the solid.

Question 3

As sound waves need _______ to be transmitted, the more ______ a solid is, the _______ sound will travel through it

Answer 3

particles, dense, faster

Question 4

Sound cannot do what in a vacuum? why

Answer 4

Travel. Because there are no particles in a vacuum

Question 5

As sound travels from one medium to another and becomes faster/slower, _______ remains the same. What does this cause and 1 example

Answer 5

Frequency remains the same.

Wave speed = Frequency x Wavelength

As the speed of sound changes, frequency remains the same so we know wavelength increases or decreases with speed. Therefore, wavelength will be longer in a denser material

Question 6

Like light, sound waves can be ______, ________ or ______

Answer 6

refracted, absorbed or reflected

Question 7

What causes echoes

Answer 7

The reflection of sound waves on hard, flat surfaces

Question 8

What does amplitude and frequency change in terms of the sound

Answer 8

Higher amplitude = louder sound
Higher frequency/shorter wavelength = Higher pitch

Question 9

What sound frequency can humans hear

Answer 9

20 Hz - 20,000 Hz