Question

Calculate by which current will change when doubling the voltage without changing the resistance of the conductor. Assume ohmic conductor.
A) Decrease by factor of 2
B) Decrease by factor of 4
C) Increase by factor of 2
D) Increase by factor of 4

Answer 1

Hint: Ohm law states that the voltage across a conductor is directly proportional to current through conductor. Means if we change the current through a conductor then voltage across the conductor changes by the same factor by which current changed. Similarly, if voltage is changed then current also changed.

Complete step by step answer:
We have given that the voltage is doubled up and conductor is ohmic means it follows ohm's law of electricity. Main property of an ohmic conductor is that the resistance of the conductor remains the same.
Ohm law states that the voltage across a conductor is directly proportional to current through the conductor. Means when voltage across a conductor is changed by some factor x then current also changed by factor.
As given voltage is doubled means voltage is increased by factor 2 then current also increases by factor 2.
Hence current is increased by factor of 2.
So, the correct answer is option C.

Note: If we have a non-ohmic conductor and double its voltage then current may not be increase by factor of 2 because the resistance conductor increased with increase in temperature and we know that when current pass through a conductor then its resistance increases and due to which change in current also depends on temperature of conductor.