A teacher places a metal can on top of an insulating foam cup and touches the side of the cup with a negatively charged rod. The setup is shown in the picture below.

Question

What will happen to the negatively charged electrons when the rod touches the foam cup?

(1 point)
Responses

The electrons will transfer from the cup to the metal can, causing both cup and can to have a positive charge.
The electrons will transfer from the cup to the metal can, causing both cup and can to have a positive charge.

The electrons will transfer from the cup to the metal can, causing both the cup and can to have a negative charge.
The electrons will transfer from the cup to the metal can, causing both the cup and can to have a negative charge.

The electrons will transfer to the cup and will remain in a concentrated, positively charged area on the cup where the rod was placed.
The electrons will transfer to the cup and will remain in a concentrated, positively charged area on the cup where the rod was placed.

The electrons will transfer to the cup and will remain in a concentrated, negatively charged area on the cup where the rod was placed.
The electrons will transfer to the cup and will remain in a concentrated, negatively charged area on the cup where the rod was placed.
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Answer 1

When the negatively charged rod touches the insulating foam cup, the excess electrons from the rod will not transfer to the cup because the foam is an insulator. Instead, when the rod touches the cup, it will induce a separation of charges within the cup.

However, since you are specifically asking about the transfer of electrons when the rod touches the cup, the most accurate response would be:

The electrons will transfer to the cup and will remain in a concentrated, negatively charged area on the cup where the rod was placed.

This option correctly describes that the cup becomes negatively charged due to the extra electrons from the rod, leading to an accumulation of negative charge in the area of contact.