Q. In the circuit shown in figure-$3.366$, reading of ammeter will

Current Electricity Report Error

A

Increase if $S_{1}$ is closed

B

Decrease if $S_{1}$ is closed

C

Increases if $S_{2}$ is closed

D

Decrease if $S_{2}$ is closed

Solution:

By closing switch $S_{1}$, net external resistance will decrease this increases the circuit current so ammeter reading will increase.
By closing $S_{2}$, equivalent EMF will remain unchanged but equivalent internal resistance of battery will decrease and this increases the circuit current so ammeter reading will increase.

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