Ohm's law expresses the relationship among which quantities?

Ohm's law expresses the relationship among which quantities?

• A. Ohm's law
• B. Lenz's law
• C. Joule's law
• D. Faraday's law

Answer: (A)

Voltage, current, and resistance relate in a straightforward way for many conductors: when a voltage is applied across a resistor, the current through it changes in proportion to that voltage, with the resistance setting the proportionality. This is captured by V = IR, so current is V divided by R and voltage is IR. If the material is ohmic and temperature remains roughly constant, the relationship is linear, meaning the resistance stays constant across the range you’re measuring. The other laws describe different phenomena: Lenz's law concerns the direction of induced current to oppose a change in magnetic flux; Joule's law explains how electrical energy turns into heat in a conductor (P = I^2R or P = V^2/R); Faraday's law describes how a changing magnetic flux induces an electromotive force.

Voltage, current, and resistance relate in a straightforward way for many conductors: when a voltage is applied across a resistor, the current through it changes in proportion to that voltage, with the resistance setting the proportionality. This is captured by V = IR, so current is V divided by R and voltage is IR. If the material is ohmic and temperature remains roughly constant, the relationship is linear, meaning the resistance stays constant across the range you’re measuring.

The other laws describe different phenomena: Lenz's law concerns the direction of induced current to oppose a change in magnetic flux; Joule's law explains how electrical energy turns into heat in a conductor (P = I^2R or P = V^2/R); Faraday's law describes how a changing magnetic flux induces an electromotive force.