Metre Bridge

The metre bridge uses the Wheatstone bridge principle to measure an unknown resistance.

It consists of a uniform wire AB 100 cm long; the ends are soldered to two copper or brass strips, S₁ and S₂ , with the wire stretched over a calibrated scale. The third strip or plate is placed parallel to the wire.

The unknown resistance R1 and known resistance R2, are connected across the gaps. By closing the key, the jockey is moved along