Lecture Demonstration Laboratory LDL Home» Optics» Photometry» Luminosity

Inverse Square Law

Set up the grid board and an optical rail so that when the black square is at the far end of the rail, its shadow covers one 4x4-cm square on the board. Each time the distance between the square and the light source reduces in half, the shadow increases to four times the area.


Optical Rail
2 Sliding Carriages
1-in Square Barrier
Optical Cable Lamp
Chalkboard Grid

Lecture Demonstration Laboratory

 Login to add a review

Lecture Demonstration Laboratory
History of Use

1 total uses

2013   Fall      ASTR 2010   001     Modern Cosmology      Julie Comerford     9/11/2013