Whose value remains constant in defining Ohm's law?

Correct option is D

(d) Temperature

In Ohm's law, the temperature remains constant for the law to hold true.

• Ohm's law is represented as V = IR, where:
  • V is the voltage across a conductor,
  • I is the current flowing through the conductor,
  • R is the resistance of the conductor.
• The resistance of most materials depends on temperature, so in order to apply Ohm's law, temperature must remain constant. If temperature increases, resistance may change, which could cause deviations from Ohm's law.

Information Booster:

1. Temperature plays a significant role in the behavior of conductors and their resistance.
2. Current (option b) and pressure difference (option c) are variables in Ohm's law, not constants.
3. Pressure (option a) is unrelated to Ohm's law, as it applies to fluid dynamics, not electrical resistance.

Additional Information:

• In non-ohmic conductors, such as semiconductors, the resistance is not constant and can change with temperature, making Ohm's law inapplicable in those cases.