On a day when the speed of sound is 354 m/s, a 2000 Hz sound wave impinged on two slits 30 cm apart. At what angle is the first max located?
I just am not sure what equation to use. any help is appreciated..im lost
The equation to use is the same one as Young's double-slit diffraction equation for light, except that you have to use the wavelength of sound instead of light. The wavelength in this case is
L = (speed of sound)/(frequency) = 0.177 m
The first maximum is the zero order, perpendicular to the plane containing the two slits. They probably want you to determine where the next maximum (first order) is. That angle is given by
theta =
(wavelength)/(slit separation)
= 0.177/0.30 = 0.59 radians = 34 degrees
reference:
http://en.wikipedia.org/wiki/Double-slit_experiment