Question

If the resistance in a circuit connected to a constant current is halved, how is the voltage in the circuit affected?The voltage remains constant.The voltage is doubled.The voltage is reduced by a factor of 4.The voltage is reduced by a factor of 2.The voltage is quadrupled.

Answer 1

The voltage is reduced by a factor of 2.

Step-by-step explanation:

According to the OHM's law, Voltage is directly proportional to the resistance keeping the current constant

Voltage = Current × resistance

V = I × R

when I is constant, V ∝ R

It can be seen that by keeping the current constant, as we halved the resistance, voltage will be halved.

For Example

Consider, I = 10 A R = 10Ω

then V = I × R = 10 × 10 = 100 V

Keeping current constant and by halving the resistance i.e R = 5Ω

V = I × R = 10 × 5 = 50 V

Hence, resistance in a circuit is halved, Voltage will be halved.