Sound source of frequency 170 Hz is placed near a wall. A man walks from the source to the wall and finds periodic rise and fall in sound intensity.Speed of sound in air is 340m/s.
Distance separating two adjacent minimum intensity positions in metres is?
I get the (correct)answer 1 if I consider standing waves but I want to know if and how beats will be produced here and if that concept is used.

Question

Sound source of frequency 170 Hz is placed near a wall. A man walks from the source to the wall and finds periodic rise and fall in sound intensity.Speed of sound in air is 340m/s.
Distance separating two adjacent minimum intensity positions in metres is?
I get the (correct)answer 1 if I consider standing waves but I want to know if and how beats will be produced here and if that concept is used.

lastdaywork · Answer

I think beats and standing waves will give the same answer. But to be sure, I need to revise my notes (and I am wasted right now).
@Mashy ;
@Vincent-Lyon.Fr ;
@douglaswinslowcooper

anonymous · Answer

$$\phi(x,t)=j(vector)\sin(2\pi vt/\lambda) \cos(2\pi x/\lambda) $$

anonymous · Answer

|dw:1390310539641:dw|
represents
a transverse standing wave how?