Question

A high speed rail train is approaching a crossing in South Florida. Because the train is approaching, a Doppler shift will cause

the sound of the train's horn to be louder
the sound of the train's horn to be louder and appear to be at a lower pitch
the sound of the train's horn to appear to be at a lower pitch
the sound of the train's horn to appear to be at a higher pitch

Answer 1

Explanation: The correct answer is: the sound of the train's horn to appear to be at a higher pitch.

As the high speed rail train approaches the crossing, it moves towards the sound waves it creates. This causes the frequency of the sound waves to be compressed, which results in an apparent increase in frequency or pitch of the train's horn. This effect is known as the Doppler shift. Therefore, the sound of the train's horn will appear to be at a higher pitch.