Resonance, Doppler Effect

An observer moves towards a source of sound at a speed of 30 ms-1

If the frequency of the sound to a stationary observer is 500 Hz the frequency to the moving observer is

• 456 Hz

• 544 Hz

• 460 Hz

• 548 Hz

Tags

CCSS.HSA.REI.B.3

CCSS.HSA.SSE.A.1

An observer passes a 500 Hz sound source and moves away with a speed of 30 ms-1.

The frequency heard by the moving observer is

• 456 Hz

• 544 Hz

• 460 Hz

• 548 Hz

Tags

CCSS.HSA.REI.B.3

The observer throws the 500 Hz sound source back at a speed of 40 ms-1 . The frequency of the source as observed by A is now

• 447 Hz

• 358 Hz

• 320 Hz

• 300 Hz

Observer A listens to source of sound moving at 60 ms-1 towards her.

If the frequency of the sound to an observer stationary relative to the sound is 500 Hz what is the frequncy to A.

• 607 Hz

• 425 Hz

• 2800 Hz

• 800 Hz

Tags

CCSS.HSA.REI.B.3

CCSS.HSA.CED.A.1

What best describes the doppler effect?

• An apparent change in frequency of a wave due to the relative motion between a wave source and an observer
• When sound changes pitch
• When light changes color
• An apparent change in the amplitude of a wave due to the relative motion between a wave source and an observer.

When a train passes by an observer, the frequency seems to change. This is an example of _________.

• Resonance

• The speed of sound

• The Doppler Effect

• Intensity

A stationary observer hears a sound emitted by a moving source. This produces a Doppler effect which is a

• change in frequency of the sound emitted by the source

• change in frequency of the sound heard by the observer

• change in velocity of the sound emitted by the source

• change in velocity of the sound heard by the observer

A source of sound of constant frequency is moving towards an observer. Compared to the frequency of the source, the frequency of sound heard by the observer is

• higher, because the speed of sound increases

• lower, because the air is compressed

• higher, because the wavelength of the sound decreases

• lower, because the amplitude increases