Seberkas cahaya monokromatik dijatuhkan pada kisi difraksi dengan 5000 goresan/cm menghasilkan spectrum garis terang orde kedua membentuk sudut 30 derajat terhadap garis normalnya. Panjang gelombang cahaya yang digunakan adalah …. *

500 nm

Explanation:

In this problem, we have a diffraction pattern created by light passing through a diffraction grating.

The formula to find a maximum in the pattern produced by a diffraction grating is the following:

where:

d is the distance between the lines in the grating

is the angle at which the maximum is located

m is the order of the maximum

is the wavelength of the light used

In this problem we have:

is the angle at which is located the 2nd-order bright line, which is the 2nd maximum

n = 5000 lines/cm is the number of lines per centimetre, so the distance between two lines is

Re-arranging the equation for , we find the wavelength of the light used:

6 cos 34, 6 sin 34 trig