wiz-icon
MyQuestionIcon
MyQuestionIcon
1
You visited us 1 times! Enjoying our articles? Unlock Full Access!
Question

A single slit diffraction pattern is formed with white light. For what wavelength of light, the third secondary maximum in the diffraction pattern coincides with the second secondary maximum of red light in the pattern. Take wavelength of red light as 6500 ˚A?

A
8840 ˚A
No worries! We‘ve got your back. Try BYJU‘S free classes today!
B
4120 ˚A
No worries! We‘ve got your back. Try BYJU‘S free classes today!
C
4640 ˚A
Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses
D
6420 ˚A
No worries! We‘ve got your back. Try BYJU‘S free classes today!
Open in App
Solution

The correct option is C 4640 ˚A
For a secondary maxima, a sinθ=(2m+1)λ2
For 2nd secondary maxima using red light,
asinθ1=5λ12sinθ1=5λ12a...(i)

For third secondary maxima using the unknown wavelength,
asinθ2=7λ22sinθ2=7λ22...(ii)

Since, these positions coincide with each other for unknown wavelength and red light,
sin θ1=sin θ2

5λ12a=7λ22a
λ2=57λ1=57×6500
λ24640 A

Hence, (C) is the correct answer.

flag
Suggest Corrections
thumbs-up
0
Join BYJU'S Learning Program
similar_icon
Related Videos
thumbnail
lock
Diffraction I
PHYSICS
Watch in App
Join BYJU'S Learning Program
CrossIcon