SUBTOPIC 8.3: DOPPLER EFFECT

Question 1

When an ambulance with a siren passes by you, the pitch of the sound seems higher as it approaches and lower as it moves away. What causes this change in pitch?

Accepted Answer

3

Question 2

The Doppler Effect depends on:

Accepted Answer

1

Question 3

When a sound source is moving TOWARDS an observer, what happens to the perceived frequency of the sound?

Accepted Answer

1

Question 4

Consider a stationary observer and a sound source moving away. The observer will hear a sound that is

Accepted Answer

1

Question 5

If both the source and observer are stationary, what happens to the observed frequency?

Accepted Answer

3

Question 6

In radar speed guns used by police, the Doppler Effect is used to measure the speed of vehicles. How does it work?

Accepted Answer

3

Question 7

If the observer moves toward a stationary source, what happens to the observed wavelength?

Accepted Answer

1

Question 8

When the source of sound moves away from the observer, what happens to the wavelength and frequency observed?

Accepted Answer

0

Question 9

Which of the following situations will produce the largest Doppler shift?

Accepted Answer

1

Question 10

A train emits a whistle at 400 Hz as it approaches a tunnel wall. The reflected sound (echo) heard by the train driver has a frequency slightly higher than 400 Hz. Why?

Accepted Answer

3