0:00
Hello students.
00:01
So in this question we need to find the frequency for the given cases.
00:05
For that, let us write the doppler's effect.
00:10
According to doppler's effect, the formula is given as frequency of listener fl equals v speed of sound plus minus vl speed of listener divided by v plus minus vs which is speed of source.
00:32
Multiply by f s that is frequency of source.
00:35
Now using this formula, we can solve all the cases given in the statement.
00:40
So for case a, we are given with the condition that listener moves towards the source.
00:49
So for that case, vl will be positive.
00:54
So in this case, we are also given with vs is zero and vl is 29 meter per second.
01:02
Now putting the values, we get the fl equals.
01:07
Now, v here is 340 plus vl is positive, so plus 29 divided by 340 plus 0.
01:20
Multiply by fs is given 1 .1 .25 hertz.
01:25
So after calculating, we get the result 1 -2 -1 -1 hertz.
01:29
So the final answer for part a will be given as fl.
01:34
That is frequency of the listener is 1 221 hertz...