A sheet of glass is coated with a 504-nm-thick layer of oil (n = 1.42). Part A F
ID: 1495865 • Letter: A
Question
A sheet of glass is coated with a 504-nm-thick layer of oil (n = 1.42). Part A For what visible wavelengths of light do the reflected waves interfere constructively? Express your answer numerically. If there is more than one answer, enter your answers in ascending order separated by commas. Part B For what visible wavelengths of light do the reflected waves interfere destructively? Express your answer numerically. If there is more than one answer, enter your answers in ascending order separated by commas.
Explanation / Answer
d = 504 nm
n = 1.42
For constructive interference,
n*d = m*
1.42 * 504 = 1 *
= 715.68 nm
n*d = m*
1.42 * 504 = 2*
= 357.84 nm
Visible wavelengths of light do the reflected waves interfere constructively, = 715.68 nm
For destructive interference p.d. = 1/2 or 3/2 wavelengths
n*d = m*
1.42 * 504 = 1/2 *
= 1431.36 nm
n*d = m*
1.42 * 504 = 3/2 *
= 477.12 nm
Visible wavelengths of light do the reflected waves interfere destructively, = 477.12 nm