Question

b. W ch material is used for the metre bndge wire and why.
8) Two cells of emf E, and E, are connected together in two ways shown in fig.
E
E
E
The balance points' in a given potentiometer experiment for these two combinations of cells
to be at 351 cm and 70.2 cm respectively. Calculate the ratio of emf of the two cells.​

Answer 1

Explanation:

(a) The connection between the resistors in a meter bridge is made of thick copper strips because the resistivity of a copper wire is very low. As, the connections are thick, so the area becomes large and the resistance of the wires becomes almost negligible.

(b) It is preferred to obtain the balance point in the middle of the meter bridge wire because it improves the sensitivity of the meter bridge.

(c) Constant is used for meter bridge wire because its temperature coefficient of resistance is almost negligible due to which the resistance of the wire does not get affected on increasing temperature of the wire during flow of current.