doppler effect

we need to hear this while we are following the source and slowly getting farer behind it

is : the pitch getting lower . same as it is getting quieter ?

No, no. Loudness is related to amplitude, not pitch. Pitch depends on Frequency. the lower the frequency, the lower the pitch.

but the further away the source is . the lower pitch .. and also lower volume =/

The lower frequency is not because the source is farther away but because the the source is moving in the opposite direction.

The frequency changes because the source emits the wave and then moves away from the wave before emitting the next one causing the overall frequency to be lower.

thanks man u just did my science hw for me lol

thanx u did my science hw 4 me lol

now i can just ride ma horse all day

but why are the sound waves crowded?

Because the source creating the sound waves is in motion. Essentially, after one sound wave is emitted, the source "makes ground" on that wave so the next emitted wave is closer to it.

koool thanks :)