Which of these events is an example of the Doppler shift?

The amplitude of a wave on a string increases as the frequency decreases.

The amplitude of sound from a tuning fork decreases due to damping.

The frequency of light from a star increases as it moves toward us.

The intensity of an electromagnetic wave increases with the field strength.

The velocity of an electromagnetic wave changes as its medium changes.

Verified Answer :

The intensity of an electromagnetic wave increases with the field strength.

Answer;

The intensity of an electromagnetic wave increases with the field strength.

Explanation;

  • Doppler shift also Doppler effect occurs when the source of a wave form sends out waves at a regular rate or frequency, but there is a constant relative motion between the source and the observe, thus causing a change in frequency.
  • Electromagnetic waves are waves that do not require a material medium for transmission. Energy in electromagnetic waves is transferred through vibrations of electric and magnetic fields.
  • The strength of electric and magnetic field increases the intensity of an electromagnetic wave, which is an example of Doppler shift.