AIIMS2000Physics-Optics
AIIMS 2000 Physics Photometry MCQ Question
Type: MCQ-conceptual-Medium-Class 12
A good photographic print is obtained by an exposure of 2 seconds at a distance of 1 m from the lamp. How much time will be required to get equally good result at a distance 2 m from the same lamp?
A
1 second
B
2 second
C
4 second
D
8 second
Correct Answer
Option D
Detailed Explanation
The intensity of light decreases with the square of the distance. Therefore, at twice the distance, the exposure time must be increased by a factor of four, resulting in 8 seconds.
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