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Question
Figure shows a glowing mercury tube. The intensities at point A, B and C are related as __________ .
Options
B > C > A
A > C > B
B = C > A
B = C < A
Solution
B = C < A
Here, since B and C have the same distance and lie inclined to make the the same vertical angle with the source, they will have same intensity. But, as A is nearer and forms an angle of 0° with the source, intensity of A will be greater than C or B.
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