What is most likely the color of the light whose second-order bright band forms an angle of 13.5° if the diffraction grating has 175 lines per mm?

Answer : The color of light is red.

Explanation :

Given that,

Numbers of lines in a diffraction grating, n = 175 lines per mm

The grating equation for the bright band is given by :

d sinФ = n λ

Where,

d is the distance between the slits

Ф is the angle to maxima

n is the order, n = 2

λ is the wavelength of the light.

Since, d = 1/N

N is the numbers of lines

So,

converting mm to m

λ = 6.66 × 10⁻⁷ m

or

λ = 667 nm

This shows the wavelength of red light. So, the color of light emitted will be red.

Hence, this is the required solution.

technology is the application of the knowledge gained by science.