The relationship between irradiance, \(I\), and distance, \(d\), can be shown to follow an inverse square law. \(I=\frac{k}{d^{2}}\) The product of irradiance and the square of the distance from ...

A lamp illuminates a screen of area \(2.0m^{2}\), which is \(4 m\) away. The irradiance at the screen is \(0.02Wm^{-2}\). a) Calculate the power of the incident beam. b) If the screen is moved to ...