A circular satellite dish reflector of diameter is viewed face-on from a control…

PHYSICS · Subjective · Fermi University Physics · Optics & Photonics · Geometrical optics and imaging · Geometrical optics and imaging

Optics and Photonics, Ch Radiometry and photometry

Problem

A circular satellite dish reflector of diameter

3.2\ \mathrm{m}

is viewed face-on from a control tower

800\ \mathrm{m}

away. The dish is small compared with this distance. Find the solid angle the dish subtends at the tower.