Sunlight of intensity is incident normally on a thin convex lens of focal length 20 cm
PHYSICS · Subjective · AP · Physics 2: Algebra-based · Waves Sound and Physical Optics · Waves Sound and Physical Optics
Problem
Sunlight of intensity 1.3 kW m−2 is incident normally on a thin convex lens of focal length 20 cm. Ignore the energy loss of light due to the lens and assume that the lens aperture size is much smaller than its focal length. The average intensity of light, in kW m−2 , at a distance 22 cm from the lens on the other side is _____. [Adv. 2018]