Question

A magnet and a coil are oriented as shown in (Figure 1) . The magnet is moved rapidly into the coil, held stationary in the coil for a short time, and then rapidly pulled back out of the coil.

A magnet and a coil are oriented as shown in (Figure 1) . The magnet is moved rapidly into the coil, held stationary in the coil for a short time, and then rapidly pulled back out of the coil. Choose the correct graph of the reading of the ammeter as a function of time. The ammeter registers a positive value when current goes into the + terminal.

Choose the correct graph of the reading of the ammeter as a function of time. The ammeter registers a positive value when current goes into the "+" terminal.

A.

B.

C.

D.

Answer 1

According to lenz law, the induced current opposees the cause. that is, the induced current in the loop while the magnet is entering into the loop, is in anti clock wise. that is it is a positive peak. the induced current in the loop while the magnet passes away fromn the loop is clock wise. that is negative peak.

therefore, the correct gaph is figure (B).