Multiple Choice
If you rub a balloon on your sweater and then press it to a wall,it will often stick there.Why does this happen?
A) Rubbing removes a surface layer of grease,allowing the rubber to come in sufficiently close contact with the wall so that air pressure holds it there.
B) Rubbing the balloon charges it electrostatically,and this charge on the balloon induces an opposite charge on the wall.The attraction between the induced charge and the charge on the balloon holds the balloon to the wall.
C) A wall typically has a net electric charge on it,and rubbing the balloon charges it electrostatically.If the wall happens to have opposite charge to that on the balloon,the balloon will stick.
D) Rubbing the balloon causes moisture to condense on it,and surface tension causes the balloon to stick to the wall.
E) Rubbing the balloon surface causes it to become slightly conducting.When the balloon is touched to the wall,electrons flow from the balloon to the wall.This sets up an electric field that bonds the balloon weakly to the wall.
Correct Answer:

Verified
Correct Answer:
Verified
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