A spacer is cut from a playing card of thickness 2.79 x 101 m and used to separate one end of two rectangular, optically flat, 2.80 cm long glass plates with n = 1.70, as in the figure below. Laser light at 543 nm shines straight down on the top plate. HINT Adjacent dark bands occur when the air gap thickness changes by half a wavelength. Click the hint button again to remove this hint. (a) Count the number of phase reversals for the interfering waves. 1027 X (b) Calculate the separation (in m) between dark interference bands observed on the top plate. (No Response) m

A spacer is cut from a playing card of thickness 2.79 x 101 m and used to separate one end of two rectangular, optically flat, 2.80 cm long glass plates with n = 1.70, as in the figure below. Laser light at 543 nm shines straight down on the top plate. HINT Adjacent dark bands occur when the air gap thickness changes by half a wavelength. Click the hint button again to remove this hint. (a) Count the number of phase reversals for the interfering waves. 1027 X (b) Calculate the separation (in m) between dark interference bands observed on the top plate. (No Response) m