Which of the following statements best describes how Lenz’s law upholds the principle…
PHYSICS · Single correct · A Level · Physics · Fields and their consequences · Fields and their consequences
Problem
Which of the following statements best describes how Lenz’s law upholds the principle of conservation of energy?
(a) It guarantees that the induced current always aids the change in magnetic flux, thereby producing energy.
(b) It claims that the magnitude of the induced emf depends only on the magnetic flux itself, not on how fast the flux changes, so no energy input is needed.
(c) It ensures that the induced current opposes the change in magnetic flux, so an external agent must supply work and total energy is conserved.
(d) It says that the direction of the induced current is fixed by the physical orientation of the conductor inside the field; energy considerations are secondary.