Question

to find resistance of given wire using metre bridge and hence determine the (spcific resistance ) of its material.

Answer 1

Aim

To find resistance of a given wire using metre bridge and hence determine the resistivity (specific resistance) of its material.

Apparatus

A metre bridge (slide wire bridge), a Leclanche cell (Battery eliminator), a galvanometer, a resistance box, a jockey, a one way key, a resistance wire, a screw gauge, a metre scale, a set square, connecting wires and a piece of sand paper.

Theory

(i) The unknown resistance X is given by

to-find-resistance-of-a-given-wire-using-metre-bridge-and-hence-determine-the-resistivity-specific-resistance-of-its-material-1

where, R is known resistance placed in the left gap and unknown resistance X in the right gap of metre bridge. I cm is the length of metre bridge wire from zero end upto balance point.

(ii) Specific resistance (p) of the material of the given wire is given by

to-find-resistance-of-a-given-wire-using-metre-bridge-and-hence-determine-the-resistivity-specific-resistance-of-its-material-2

where, L is the length and D is the diameter of the given wire.

Answer 2

Metre bridge:

Explanation:

• meter bridge in hindi Meter Setu is a device based on the principle of Wheatstone.
• With the help of which we can find the resistance of a conductor wire. The meter bridge is also used to find the value of unknown resistances, just like Wheatstone.
• In the formula p = Sπr2/L – the specific resistance of the wire material by taking the value of the resistance S, radius t and length L of the wire in ohm-cm. Let us know.
• After this, by dividing the value of 100, it is converted into an ohm-meter.