Question

A balloon is initially electrostatically neutral. It is then rubbed on against a sweater. The balloon now has a large net negative charge. Consider the mass and volume.

• A. The mass would increase slightly while the volume would stay the same.
• B. The volume would increase slightly while the mass would stay the same.
• C. Both the mass and volume would increase slightly.
• D. Neither the mass or the volume would increase slightly.

Answer 1

The correct option is A The mass would increase slightly while the volume would stay the same.

The negative charge is obtained by the balloon due to gain of electrons from the sweater. Hence the mass of electrons gets added to the previous mass, increasing the mass of balloon.

However the volume of the balloon remains the same, the charge does not affect the size of the balloon.