Question

A student is provided with a rubber cylinder and a patch of synthetic fur. The rubber cylinder and the patch are electrically neutral. The student rubs the cylinder back and forth along the fur. A short time later, after the cylinder and fur have been placed on insulating stands, the student determines that the fur has a net negative electric charge. Before the patch of fur attained its net negative charge, it was considered to be electrically neutral. Which of the following claims, with appropriate evidence, is correct about the distribution of charge in the patch of fur before the charging process?

a. It is an isolated system.
b. It is a closed system.
c. It is an open system.
d. The type of system cannot be determined unless information is known about the net force exerted on the system at any given time.

Answer 1

Option b ( It is a closed system) is the appropriate answer.

Step-by-step explanation:

• The mass transfer isn't made on a platform. There seems to be no mass transfer, the mechanism can't be separated as power lines will interfere beyond the physical boundaries including its fur patch.
• The mechanism can't however be separated and, while the mass transfer is indeed not present, several field lines will communicate well outside the mechanism.

The other options are not linked to the situation in question. Thus, the answer is correct.