Objective:
– To show induction of current in a conductor moving in a magnetic fields.
Apparatus:
- rolling rod assembly (see figure below)
- strong U magnet (as for DEM44)
- O.H.P. galvanometer (scale 100-0-100 µA) or equivalent
- 2 long leads
Method:
Set up the apparatus as shown above. The O.H.P. galvanometer is connected in series with the terminals of the rolling rod assembly. When the rod is allowed to roll down the rack towards the magnet, it cuts the magnetic field and a current is induced in the rod.
Note:
This demo can be done in conjunction with DEM31.1 (Force on a current-carrying conductor) since they both use the rolling rod assembly.
A fluke 8050A set to the 200 µA range could be substituted for the galvanometer if desired.