Question

A fire truck with its siren blowing passes you. What happens to the sound of its siren as the truck moves away from you?

A. the pitch gets higher
B. the pitch gets lower
C. the amplitude gets higher
D. the amplitude gets lower

Answer 1

here the Doppler effect is involved

Answer 2

ok! what does that mean? :/ pitch gets lower?

Answer 3

since the source of the sound is going away from me, then the received frequency from me, is less than the emitted frequency by the truck

Answer 4

ohh so the solution should be amplitude is lower? choice D?

Answer 5

I think that the answer is
the pitch gets higher, since we have the subsequent relationship between wave length and frequency:
\[\Large \lambda = \frac{v}{\nu }\]
where v is the speed of sound

Answer 6

ohhh okay! makes sense :)

thank you!!!

Answer 7

:)