Q. A bat emits a sound whose frequency is 91.20 kHz. The speed of sound in air at 20 degrees Celcius is 343m/s. However the air temperature is 38.8 degrees Celcius, so the speed of sound is not 343m/s. imagine that air behaves like an ideal gas, and finds wavelength of the sound.
Q. Coherent light with wavelength 593 passes through two very narrow slits, and the interference pattern is observed on a screen a distance of 3 from the slits. The first-order bright fringe is a distance of 4.84 from the center of the central bright fringe. For what wavelength of light will first-order dark fringe be observed at this same point on the screen?