If a source of sound waves is rapidly approaching a person, the sound heard by the person appears to have

A. a period higher than the original period.
B. an amplitude lower than the original amplitude.
C. a frequency higher than the original frequency.
D. a pitch lower than the original pitch.

Question

If a source of sound waves is rapidly approaching a person, the sound heard by the person appears to have 
    
   A. a period higher than the original period.
   B. an amplitude lower than the original amplitude.
   C. a frequency higher than the original frequency.
   D. a pitch lower than the original pitch.

anonymous · Answer

the answer is not D

anonymous · Answer

What do you think?

anonymous · Answer

honestly im so lost idk anymore maybe c?

anonymous · Answer

Yes! You Are Correct! Great Job!

anonymous · Answer

A pitch/frequency higher/shorter than the original. This is usually referred to as the "Doppler Effect". The reason is that the wave generated by the sound has the relative velocity of the moving object added to its own velocity, changing the relative perception of the wave by the stationary listener. 

Note that this answer applies to light waves, but in a slightly different way, since the velocity of light is always a constant.

anonymous · Answer

thank you so much for your help!!!!