Question

Gives reasons :
(i) The wires in the coil of resistance box are turned twice.
(ii) In Wheatstone bridge, initially a cell key and later galvanometer is pressed.

Answer 1

Explanation:

(i) Generally wires in the resistance box are double folded and then coiled to nullify inductance effect. ... Because of this Magnetic induction caused by one half of the wire is cancelled by the magnetic induction caused by other half of the wire and keeping the wires with pure resistance.

(ii) In the experiment of wheat stone bridge first we pressed cell key and then galvanometer. ... If key of galvanometer is first pressed then the key of cell then a large emf is induced due to which main current aquires its constant value after sometime .