A 2000 Hz sound wave passes through a wall with two narrow openings 30 cm apart. If sound travels on average 348 m/s, find the following.  If the slit separation is 1.00 µm, what frequency of light gives the same first order maximum angle?

Sound waves with frequency 2600 Hz and speed 343 m/s diffract through the rectangular opening of a speaker cabinet and into a large auditorium of length 100 m. The opening, which has a horizontal width of 38.7 cm, faces a wall 100 m away (the figure below).   Along that wall, how far from the central axis of that wall in meters will a listener be at the first diffraction minimum and thus have difficulty hearing the sound? (Neglect reflections.)

A screen is placed 50.0 cm from a single slit that is illuminated with light of wavelength 680 nm. If the distance between the first and third minima in the diffraction pattern is 3.00 mm, what is the width of the slit?

Suppose light with wavelength 540 nm has parallel wavefronts incident on two slits that are both 0.36 mm wide, and separated by 0.5 mm. A screen is placed 1.2 m from the slit. The intensity at the optical axis is 5 mW. What is the distance from the optical axis to the second minimum on the screen in mm?