What are eddy currents?

A conducting plate moves into a magnetic field. According to Lenz's law, do eddy currents assist or oppose the motion?

An eddy current path has induced emf \(0.20\,\mathrm{V}\) and effective resistance \(0.50\,\Omega\). Estimate the current.

An eddy current of \(3.0\,\mathrm{A}\) flows through an effective resistance \(0.20\,\Omega\). Find the heating power.

Why does a magnet falling through a copper pipe fall more slowly than through air?

Why are transformer cores often laminated?

A device uses eddy currents for braking. What happens to the kinetic energy?

If an eddy current path's resistance is doubled while induced emf is unchanged, by what factor does the heating power \(P=\mathcal E^2/R\) change?

If the induced emf around an eddy-current path doubles while resistance is unchanged, by what factor does heating power change?

Why do slots cut into a conducting plate reduce eddy-current braking?

A conducting disk spins in a localized magnetic field. Why does it experience a drag torque?

Explain why eddy currents can be useful in induction cooktops.

A solid metal core and a powdered insulated core are used in alternating magnetic fields. Which has smaller eddy-current loss and why?

A metal plate is stationary in a steady magnetic field. Are eddy currents present? Explain.

A conducting plate moves through a field twice as fast. If induced emf scales with speed, how does eddy-current heating scale in the same current path?

Why does eddy-current braking become weak at low speed?

A falling magnet reaches terminal speed in a conducting tube. Explain the force balance.

Use energy conservation to explain why a stronger eddy-current brake heats more strongly.

A conductor is cooled so its resistance decreases. For a fixed induced emf around an eddy-current path, what happens to current and heating power? State a caveat.

A perfect conductor moves into a magnetic field. Explain why the idealized limit is subtle compared with ordinary eddy-current braking.