Question

A diffraction grating is illuminated with yellow light. The diffraction pattern seen on a viewing screen consists of three yellow bright spots, one at the central maximum (θ = 0°) and one on either side of it at θ = ±50°. Then the grating is simultaneously illuminated with red light. Where a red and a yellow spot overlap, an orange spot is produced. The new pattern consists of __________

Answer 1

Answer:

an orange fringe at 0°, yellow fringes at ±50° and red fringes farther out.

Explanation:

In the visible spectrum- red to violet, red has the highest wavelength.

The maximum internsity  for diffraction grating is given by,

Sinθ$(_{max} )$ = mλ/d

It is concluded that the angle of diffraction increases with increase in wavelength'λ' .  So, red fringe will be farthest from the center, orange light will be at the center and yellow fringe will be at 50°.

Therefore, The new pattern consists of : an orange fringe at 0°, yellow fringes at ±50° and red fringes farther out.