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## Homework Statement

A point source emits visible light isotropically. Its luminous flux is 0.11 lumen. Find the flux whithin the cone that has half angle of 30 degree from the light source.

## Homework Equations

luminous flux = luminous intensity * solid anlge

## The Attempt at a Solution

I tried to divide the flux 0.11lumen by 4pi and then multiply the solid angle. But since the solid angle of the cone is 0.84sr, the result appears to be smaller than the luminous intensity. But I don't understand the result. Can the flux of finite solid angle be smaller than luminous intensity?