Thermal Expansion Of Aluminum - Optical Lever

Purpose

To demonstrate thermal expansion in a complicated way.
 

Equipment

Aluminum tube, iron lever, magnet, mirror, mounted laser and scale.

 

Setup Time

5 min.
 

    Images

    i1-14

    Description

    A small mirror with an iron lever attached to it rests on one end of an aluminum tube. The other edge of the lever rests on the pole of a magnet. When the aluminum tube is heated with a burner the mirror is deflected. To measure this deflection a laser beam is reflected off the mirror onto a scale as shown in the picture. When the tube is heated the laser spot is deflected about 50 cm when the distance between the mirror and the scale is about 2 m.