School of Physics Lecture Demonstration Manual

Ee-2 The Alternating Current Generator

Published: Tuesday 14 March 2006 - Updated: Tuesday 29 March 2011


To demonstrate the conversion of mechanical into electrical energy.



Click on pictures to enlarge.

AC Generator

AC Generator Diagram


The apparatus consists of a coil of wire free to rotate about a horizontal axis. The ends of the coil are connected to slip rings. Rotating the coil in the earths magnetic field produces an alternating e.m.f. that is displayed by the galvanometer deflections

The deflection magnitude may be increased by tha addition of a small permanent magnet beneath the coil whereupon the relationship between the field direction and induced e.m.f. becomes more obvious.

Safety notes

Electrical safety 


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