A steel magnet is inserted into a coil and demagnetised. What kind of current is produced in the coil, and in what way does the current vary?
- Aa direct current in the coil, then reduce the current quickly to zero
- Ba direct current in the coil, then reduce the current slowly to zero
- Can alternating current in the coil, then reduce the current quickly to zero
- Dan alternating current in the coil, then reduce the current slowly to zero