Waves - Light and Sound (Paper 2)

Question 1

what is the frequency range for human hearing?

Answer 1

20 – 20,000Hz

Question 2

how would you investigate the speed of sound in air?

Answer 2

• measure a distance from a sound emitter to a reflective wall
• emit a sound and measure how long it takes for the sound to return back to you
• use speed = distance/ time.

Question 3

how can an oscilloscope and microphone can be used to display a sound wave?

Answer 3

with the microphone plugged into the oscilloscope and a sound incident on the microphone, the microphone will transfer the sound into an electrical signal which the oscilloscope can display.

Question 4

how would you investigate the frequency of a sound wave using an oscilloscope?

Answer 4

• attach a microphone to an oscilloscope
• emit a sound into the microphone for one second
• count how many waves have been emitted on the screen or find how long it took for one wave to happen and use f=1/T
• this is the frequency

Question 5

how does the pitch of a sound relates to the frequency of vibration of the source?

Answer 5

high frequency means high pitch. if a sound vibrates with a higher frequency then the note sounds higher.

Question 6

how does the loudness of a sound relates to the amplitude of vibration of the source?

Answer 6

the greater the amplitude the louder the sound. bigger vibrations means more energy is being put in so more energy out as sound waves.