Magnetic Interactions in a Wire-Magnet System

[cy19861126]

Homework Statement

A magnet is hung by a string and then placed near a wire as shown. When the switch is closed, the magnet rotates such that the ends of the magnet move as indicated by the arrows. At the instant the switch is closed determine:
a) the direction of the current through the wire segment nearest the magnet.
b) the direction of the net force exerted by the magnet on the wire segment at the instant that the magnet is in the position shown.

Homework Equations

Right hand rule.

The Attempt at a Solution

a) The current will move in a clockwise direction in the perspective view because Not sure about this... Not quite good about right hand rule
b) Into the page. Not sure about this either...

 

[kuruman]

To answer this problem, you need to have a reasonable grasp of the right hand rule. If you're not good at it, you need to get better. You can still answer the question if you can figure out the direction of the magnetic field generated by the proximal straight wire. Read the section of your textbook where the B-field generated by a straight wire is discussed and how to link the direction of current flow to the circulation of the magnetic field. Pretend that the magnet is a compass needle. You know in which direction this needle will turn which gives away the direction of the B-field which gives away the direction of the current.