Q. The intensity of direct sunlight on a surface normal to the rays is $I_{0}$. What is the intensity of direct sunlight on a surface, whose normal makes an angle of $60{^\circ}$ with the rays of the sun
A) $I_{0}$
B) $I_{0}\left( \frac{\sqrt{3}}{2} \right)$
C) $\frac{I_{0}}{2}$
D) $2I_{0}$
Explanation
(c) $I_{\theta} = I_{o}\cos\theta = I_{o}\cos{60{^\circ}} = \frac{I_{o}}{2}$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.