Question

A strong magnet is placed under a horizontal conducting ring of radius r that carries current I as shown in the figure below. The magnetic field B makes an angle θ with the vertical at the ring's location. (a) what is the magnitude of the resultant magnetic force on the ring? (Use any variable or symbol stated above along with the following as necessary: π) (b) What is the direction of the resultant magnetic force on the ring? to the left to the right O upward Odownward into the screen O out of the screen

Answer 1

force on ring is given by :

$F = I\times B\times L = IB(2\pi r)$

direction from lenz's law:

a law stating that the direction of an induced current is always such as to oppose the change in the circuit or the magnetic field that produces it.

so since magnetic field is upward due to N pole so opposite to it (downward ) will be direction of magnetic field hence force.

Hence DOWNWARD