Use the domain theory to explain why a permanent magnet can be used to pick up a paperclip even though a paperclip is not a magnet.
For unlimited access to Homework Help, a Homework+ subscription is required.
One end of a bar magnet is brought close to the end of a metal bar. This metal bar might be attracted, be repelled, or experience no magnetic force. In which of these three cases can you determine that the second metal bar is also a magnet? In which cases can you determine that the second bar is definitely not a magnet? Explain your reasoning.
The magnetic field of a cylindrical magnet that has a pole-face diameter of 3.3 cm can be varied sinusoidally between 29.6 T and 30.0 T at a frequency of 15 Hz. (The current in a wire wrapped around a permanent magnet is varied to give this variation in the net field.) At a radial distance of 1.6 cm, what is the amplitude of the electric field induced by the variation?
A large superconducting magnet, used for magnetic resonance imaging, has a 50.0 H inductance. If you want current though it to be adjustable with a 1.00 s characteristic time constant, what is the minimum resistance of the system?