School of Physics Lecture Demonstration Manual

Ok-2 Echo Box With Choke Coupling

Published: Wednesday 15 March 2006 - Updated: Monday 28 March 2011

Aim

To illustrate the importance of symmetry in physics.

Apparatus

Cylinder and board as shown.

Diagrams

Click on pictures to enlarge.

Echo Box Diagram

Description

A glass tube containing water is mounted above a screen with the cryptic message "ECHO BOX WITH CHOKE COUPLING". All letters with horizontal symmetry have been coloured blue.

Safety notes

Electrical safety 

Sharps safety 

Maintenace 

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