Lenz's Law describes the direction of induced emf and current. Which statement is correct?

• A. Induced emf aligns with the change in flux
• B. Induced emf produces a current whose magnetic field opposes the change in original magnetic flux
• C. Induced emf is independent of flux changes
• D. Induced emf depends on temperature

Answer: (B)

Lenz's Law tells us that the induced current will act to oppose the change in magnetic flux through a circuit. The correct statement captures this by saying the induced emf drives a current whose magnetic field opposes the change in the original flux. In practical terms, when the external magnetic flux through the loop increases, the induced current creates a magnetic field in the opposite direction to try to reduce the net change; when the flux decreases, it produces a field in the same direction as the original to oppose the decrease. The direction is fixed by the minus sign in Faraday's law: emf = -dΦ/dt. The other options fail because emf depends on how fast the flux changes, not on temperature, and it does not simply align with the flux change.