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In producing a pure spectrum, the incide...

In producing a pure spectrum, the incident light is passed through a narrow slit placed in the focal plane of an chromatic lens because a narrow slit

A

1.a produces less diffraction

B

2.increases intensity

C

3.allows onlyone colour at a time

D

4.allows more parallel beam when it passes thorugh the lens

Text Solution

Verified by Experts

The correct Answer is:
D
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