a. A mathematical pendulum - an iron ball of mass m hanging on a long string
- has a period T₀. In the presence of a magnet placed slightly below the ball,
the period of oscillation became equal to T. Determine the magnetic force
acting on the ball.
b. An iron pendulum ball is placed between the poles of a magnet so that a
horizontal magnetic force acts on it. Find this force and the new equilibrium
position of the ball if the period of its oscillations after the magnetic field is
switched on becomes equal to T.