How many lines per mm are there in the diffraction grating if the second order principal maximum for a light of wavelength 536 nm occurs at an angle of 24 degrees with respect to the line from the grating to the center of the diffraction pattern?

To solve this problem it is necessary to apply the concepts related to the principle of superposition and the equations of destructive and constructive interference.

Constructive interference can be defined as

Where

m= Any integer which represent the number of repetition of spectrum

= Wavelength

d = Distance between the slits.

= Angle between the difraccion paterns and the source of light

Re-arrange to find the distance between the slits we have,

Therefore the number of lines per millimeter would be given as

Therefore the number of the lines from the grating to the center of the diffraction pattern are 380lines per mm

when it gains or loses electrons