Question 5 of 165
A point light source emits E.M. waves in free space. A detector, placed at a distance of m, measures the intensity as . The detector is now shifted to another location on the same spherical surface ensuring the angle between original location and new location as . The measured intensity at new location will be _______.
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Answer: (B)
For a point light source, the intensity of electromagnetic waves at a distance is given by , where is the power of the source.
Since the detector is moved to a new location on the same spherical surface, the distance from the source remains .
The emission from a point source is isotropic, meaning the intensity depends only on the radial distance from the source and is independent of the angular position.
Therefore, the intensity at the new location remains unchanged, which is .
Answer:
Since the detector is moved to a new location on the same spherical surface, the distance from the source remains .
The emission from a point source is isotropic, meaning the intensity depends only on the radial distance from the source and is independent of the angular position.
Therefore, the intensity at the new location remains unchanged, which is .
Answer: