Author Question: Assume you charge a comb by running it through your hair and then hold the comb next to a bar ... (Read 103 times)

ssal · **on:** Jul 28, 2018

Assume you charge a comb by running it through your hair and then hold the comb next to a bar magnet. Do the electric and magnetic fields produced constitute an electromagnetic wave?
1.Yes they do, necessarily.
2.Yes they do, because charged particles are moving inside the bar magnet.
3.They can, but only if the electric field of the comb and the magnetic field of the magnet are perpendicular.
4.They can, but only if both the comb and the magnet are moving.
5.They can, if either the comb or the magnet or both are accelerating.

Question 2

A student working with a transmitting apparatus like Heinrich Hertzs wishes to adjust the electrodes to generate electromagnetic waves with a frequency half as large as before. After she makes the required adjustment, what will the wavelength of the transmitted wave be?
1.four times larger than before
2.two times larger than before
3.one-half as large as before
4.one-fourth as large as before
5.none of those answers