Intensity of light.

 

A pale beam of light strikes a flat brown board. Using the controls below you can concentrate the light into a smaller beam and spread it out again.

The total amount of light does not change! Only the area of the board that the light strikes is increased or decreased.

Animation Controls:
 
Use the buttons above to control the animation.                       <go on to the next page>

Credits:
Web Page by Keith Clay
Animation by Keith Clay