Answer to Question #114343 in Electricity and Magnetism for Yang

Question

Can you verify my physic answer ?
1. A wire has current directed to your left. What direction is the magnetic field from the wire just above the wire? ==> away from you ( into the page )
2. A conductor carrying a current is arranged so that current flows away from you. If the wire is sitting in a magnetic field that points downward, what direction will the wire get pushed? ==> to the left
3. According to Faraday’s Law, what has to happen for a current to be induced in a coil of wire?
A. The coil must have a battery attached to it
B. There must must be a magnetic field through the coil
C. There must must be a changing magnetic field through the coil
D. The coil must be moving
==> C
4. The permanent bar magnet is moved to the left, toward a loop of wire. The north pole of the magnet is closer to the loop, as shown. What direction will the (induced) magnetic field be in the center of the loop of wire?
==> Right

Answer 1

1. True. Applying the right-hand rule, we see that the magnetic field lines above the wire are directed into the screen away from us.
2. Correct. The left-hand rule tells us that the force is acting to the left.
3. Correct. In the presence of an external magnetic field the answer D would be correct as well.
4. True. Applying the right-hand rule, we see that the induced magnetic field points to the right.

Well done!