Doppler Effect and Sound Frequency

The video tutorial introduces the concept of Doppler Shift, explaining how the frequency of sound waves changes when the source or observer is moving. Using the example of a train, it illustrates how sound waves compress or expand, affecting the pitch heard by an observer. The tutorial delves into the mechanics of sound wave propagation and the impact of movement on frequency, providing a comprehensive understanding of the Doppler Shift phenomenon.

What is the basic concept of the Doppler Shift?

• Change in frequency due to relative motion

• Change in sound direction with wind

• Change in sound intensity with distance

• Change in sound speed due to temperature

When a train approaches an observer, what happens to the sound frequency?

• It decreases

• It remains the same

• It increases

• It becomes inaudible

What causes the sound waves to compress when a train moves towards an observer?

• The train's speed

• The train's whistle

• The air temperature

• The observer's speed

How does the frequency change when a train moves away from an observer?

• It increases

• It decreases

• It remains constant

• It fluctuates

What is the relationship between wavelength and frequency when a sound source moves away?

• Wavelength decreases, frequency increases

• Wavelength increases, frequency decreases

• Wavelength and frequency both decrease

• Wavelength and frequency both increase

What happens to the sound frequency when an observer moves towards a stationary sound source?

• It becomes distorted

• It increases

• It remains the same

• It decreases

If an observer runs away from a stationary sound source, what happens to the frequency they hear?

• It becomes louder

• It remains unchanged

• It decreases

• It increases

What is the effect on frequency when an observer moves towards a sound source?

• Frequency increases

• Frequency remains constant

• Frequency decreases

• Frequency becomes inaudible

What is the term for the number of wave crests passing a point per unit time?

• Amplitude

• Wavelength

• Velocity

• Frequency

What happens to the sound waves when a train is right on top of an observer?

• They become silent

• They are compressed

• They are expanded

• They are neither compressed nor expanded