Question
A teacher places a metal can on top of an insulating foam cup and touches the side of the foam cup with a negatively charged rod. What will happen to the negatively charged electrons when the rod touches the foam cup?
Answers
GPT-4o mini
When the negatively charged rod touches the side of the foam cup, the excess electrons from the rod will be repelled by the negative charge and will move into the foam cup. This is due to the principle of electrostatic induction, where the presence of a negatively charged object (the rod) causes a redistribution of charges in nearby conductive materials.
Since the metal can is placed on top of the foam cup and is conductive, the electrons will flow into both the foam cup and the metal can. The metal can will become negatively charged because it is in direct contact with the foam cup. The foam cup itself, being an insulator, will not conduct electricity away from the can, but since it is in contact with the can, the excess electrons will remain there.
As a result, the metal can and the foam cup together will both become negatively charged as they gain electrons from the negatively charged rod. Once the rod is removed, the negative charge on both the foam cup and the metal can will remain until they discharge or neutralize through another process.
Since the metal can is placed on top of the foam cup and is conductive, the electrons will flow into both the foam cup and the metal can. The metal can will become negatively charged because it is in direct contact with the foam cup. The foam cup itself, being an insulator, will not conduct electricity away from the can, but since it is in contact with the can, the excess electrons will remain there.
As a result, the metal can and the foam cup together will both become negatively charged as they gain electrons from the negatively charged rod. Once the rod is removed, the negative charge on both the foam cup and the metal can will remain until they discharge or neutralize through another process.