Question
Physics Question on Ray optics and optical instruments
For light diverging from of finite point source
A
The wave front is parabolic
B
The wave front is cylindrical
C
The intensity at the wave front does not depend on the distance
D
The intensity decreases in proportion to the distance squared
Answer
The intensity decreases in proportion to the distance squared
Explanation
Solution
The intensity decreases in proportion to the distance squared: This is known as the inverse square law of light propagation. As light spreads out from a point source, the intensity (brightness) decreases as the square of the distance from the source increases. This option is correct.
So, the correct statements are: (D) The intensity decreases in proportion to the distance squared.