Iron filings are lifted by an electromagnet. The current in the electromagnet is turned off and the filings drop onto a plastic bench. A plastic comb is rubbed with a woollen cloth and then held just above the iron filings. A number of the filings leap up and cling to the comb. Which statement gives the correct explanation for the final observation?
- AThe comb has been electrically charged by rubbing with the cloth.
- BThe comb has been magnetised by rubbing with the cloth.
- CThe filings have been electrically charged by the electromagnet.
- DThe filings have been magnetised by the electromagnet.