Question

A 7.5 cm-thick layer of oil (n=1.46) is sandwiched between a 2.8 cm-thick sheet of glass and a 4.2 cm-thick sheet of polystyrene plastic (n=1.59). How long (in ns) does it take light incident 42 degrees to the normal vector to the glass to pass through this 14.5 cm-thick sandwich?.... i need to know how to figure this problem out with the 42 Degrees to the normal vector, you did the first part but forgot the 42 degrees to normal part

Answer 1

for glass Slass (15) Sin 42's 15 Sino = 26.490 so oil (146) length of paths of - light = 2.8 C05126.492 polystreene (1:59) = 3.13 cm time = distance 1-5 1. speed doing - 3.138102m similar calculation , 3x108 for oil 1.5 Sin 26.49° 1.46 since = 1.56 % 101sec o 29.270 path leyh of light = 7.5 cm - 8.44 cm. - Cos(27.29) time a distance speed = 8.44 x 16²m 3x108 7.46 = 4.11 X 10-19 sec Again. 1.46 rin 27:27 = 1.59 sina o = 24.88° path length= 4.2 cm = 4.63cm time = cos29.88) distance 4.63X10²m speed 3x108 1.59 2.45 x 10 10 se - so total time = (1.567 4.11+2.45) x10 sore = 8-12x 10 weee = 0.812 as