Question

An electric bulb is hanging over a table at a height of 1 m above it. The illuminance on the table directly below the bulb is 40 lux. The illuminance at a point on the table 1 m away from the first point will be about

(a) 10 lux

(b) 14 lux

(c) 20 lux

(d) 28 lux.

Answer 1

The correct answer is

(b) 14 lux