Doppler effect

Front

What is the Doppler effect?

Back

The Doppler effect is the change in frequency or wavelength of a wave in relation to an observer moving relative to the wave source.

Front

What happens to the wavelength when a sound source moves towards you?

Back

The wavelength becomes smaller.

Front

What happens to the wavelength when a sound source moves away from you?

Back

The wavelength becomes larger.

Front

What is redshift?

Back

Redshift is the displacement of spectral lines toward longer wavelengths in radiation from distant galaxies, indicating they are moving away from us.

Front

What is blueshift?

Back

Blueshift is the displacement of spectral lines toward shorter wavelengths in radiation from objects moving closer to us.

Front

If a listener moves towards a sound source, what happens to the perceived frequency?

Back

The perceived frequency increases.

Front

If a sound source moves away from a listener, how does the pitch change?

Back

The pitch appears lower.

Front

What is the relationship between the speed of a wave and its wavelength?

Back

The speed of a wave is equal to its frequency multiplied by its wavelength.

Front

What is the formula for calculating wave speed?

Back

Wave speed = frequency × wavelength.

Front

What is the effect of a moving observer on sound waves?

Back

A moving observer can change the perceived frequency of the sound waves.