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A person who works with large magnets sometimes places her head inside a strong field. She reports feeling dizzy as she quickly turns her head. How might this be associated with induction?

Explain why magnetic damping might not be effective on an object made of several thin conducting layers separated by insulation.

Does the resonant frequency of an AC circuit depend on the peak voltage of the AC source? Explain why or why not.

If you want a characteristic RL time constant of 1.00 s, and you have a 500 ? resistor, what value of self-inductance is needed?

Explain what causes physical vibrations in transformers at twice the frequency of the AC power involved.

Explain how electromagnetic induction can be used to detect metals? This technique is particularly important in detecting buried landmines for disposal, geophysical prospecting and at airports.

How would you shape a given length of wire to give it the greatest self- inductance? The least?

A powerful induction cannon can be made by placing a metal cylinder inside a solenoid coil. The cylinder is forcefully expelled when solenoid current is turned on rapidly. Use Faraday’s and Lenz’s laws to explain how this works. Why might the cylinder get live/hot when the cannon is fired?

Why are ordinary circuit breakers and fuses ineffective in preventing shocks?

The heart of a resting adult pumps blood at a rate of 5.00 L/min. (a) Convert this to \(\mathrm{cm}^{3} / \mathrm{s}\). (b) What is this rate in \(\mathrm{m}^{3} / \mathrm{s} ?\)