The answer is; pressure
The sound is a longitudinal wave meaning the particles vibrate parallel to the direction of the wave. Sound waves, therefore, produce compression (akin to the crest in a transverse wave) and rarefaction regions (akin to a trough in a transverse wave) as its energy is propagated in the medium.
Answer:
3 order dark fringe
Explanation:
y = Distance from central bright fringe = 204 mm
λ = Wavelength = 400 nm
L = Distance between screen and source = 1 m
d = Slit distance = 6 μm


Order of fringe is 3
So, it is a Dark order fringe