(a)[3]
Define the tesla as a unit.
(b(i))[3]
State and explain the direction of the force on the wire caused by the current.
(b(ii))[2]
Calculate the magnitude of the magnetic flux density between the poles of the magnet.
(c)[2]
A low-frequency alternating current is now passed through the wire in (b). The root-mean-square (r.m.s.) value of the current is $5.6\,\text{A}$. Describe quantitatively how the reading on the balance changes.
(ii)[2]
Calculate the magnitude of the magnetic flux density between the poles of the magnet.