Question

to hear an echo, the surface reflecting the sound wave should be at a minimum distance
of ___________
a) 3.44 m
b) 17.2 m
c) 34.4 m
d) 1.72 m​

Answer 1

Answer:

I think Option B

but not sure....

Answer 2

----HERE IS YOUR ANSWER----

Thus, for hearing the echo, the minimum distance of the obstacle from the source of sound must be half of this distance. That is,

17.2 m

----HOPE IT WILL HELP YOU----