When a conducting plate swings through a magnetic field, which is true?

a. Energy is transferred from mechanical energy to thermal energy.

b. Energy is transferred from mechanical energy to the magnetic field.

c. Energy is transferred from the magnetic field to thermal energy.

d. Energy is transferred from mechanical energy to thermal energy and then back to mechanical energy.

e. Energy is transferred from the magnetic field to mechanical energy.

Energy is transferred from mechanical energy to thermal energy and then back to mechanical energy (D)

Explanation:

when conducting plate swings through a magnetic field, energy is transferred from mechanical energy to thermal energy and then back to mechanical energy and this is due to the induction of eddy currents during the process of that the conducting plate swings through the magnetic field.

An eddy current is induced in conductor when the magnetic field in which the conductor is located varies.

Energy is transferred from mechanical energy to thermal energy. (A)

Explanation:

As the conducting plate is swinging, we know it posseses some form of mechanical energy (either K or U). Because the plate is conducting, charge is transfered, yielding energy transfer to thermal.