A bar magnet is held vertically above a horizontal metal ring, with the south pole of the magnet at the top (Figure 22.63). If the magnet is lifted straight up, will current run clockwise or counterclockwise in the ring, as seen from above?

Short Answer

Expert verified

The direction of current through the ring is clockwise direction.

Step by step solution

01

A concept:

When the current flows into the page, the magnetic field is clockwise due to the right-hand rule of thumb, we orient our thumb into the page and twist our fingers clockwise.

02

A given data:

A bar magnet is held vertically above a horizontal metal ring, with the south pole of the magnet at the top as shown in the given figure.

The magnet is lifted straight up.

03

The current run clockwise or counterclockwise in the ring:

As the magnetic field lines move towards the south pole away from the north pole, the magnetic field lines through the metal ring into the page because the north pole of the bar magnet is on the top of the ring. According to the thumb rule, the direction of the current in the ring is clockwise when the magnetic field is on the page.

Hence, the direction of current through the ring is clockwise direction.

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Most popular questions from this chapter

Two coils of wire are near each other, positioned on a common axis (Figure 22.57). Coil 1 is connected to a power supply whose output voltage can be adjusted by turning a knob so that the current I1in coil 1 can be varied, and I1is measured be ammeter 1.

Current I2in coil 2 is measured by ammeter 2. The ammeters have needles that deflect positive or negative depending on the direction of current passing through the ammeter, and ammeters read positive if conventional current flows into the + terminal. Figure 22.58 is a graph of I1vs. time. Draw a graph of I2vs. time over the same time interval. Explain your reasoning.

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