If the source moves, the wavelength of the sound in front of the direction of motion isthan the wavelength behind the direction of motion. a. the same.
b. smaller than.
c. unrealted to.
d. larger then.

B. Smaller than

Explanation:

This question is from the Doppler effect. As the object which is in motion goes off from the other, there's a reduction in the frequency. This is due to the fact that successive soundwave get to be longer. So that the pitch will then be lowered. When the person observing moves towards what is making the sound, each soundwave that follows gets faster than the previous.

a=d/t

a="triangle"v/t

explanation:

a = acceleration