(a(i))[1]
State one material that is appropriate for the core of the electromagnet.
(a(ii))[2]
Calculate the number of cells in the battery in Fig. 8.1.
(b(i))[1]
State the name of a device that can indicate the direction of a magnetic field.
(b(ii))[1]
State the name of the pole marked X on the core of the electromagnet.
(c)[3]
Calculate the potential difference (p.d.) across the solenoid.