School of Physics Lecture Demonstration Manual

Ed-1 Back EMF Due to Current of Self Induction

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

Aim

To light a fluorescent tube using a 9V battery and an inductor.

Apparatus

Diagrams

Click on pictures to enlarge.

Back EMF Diagram

Description

The switch is closed allowing current to flow through the inductor. On opening the switch the back EMF is large enough to momentarily light the fluorescent tube.

Safety notes

Electrical safety 

Maintenance 

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