GEOLOGY

Detailed explanation-1: -When you rub both balloons, both end up with negative charge. Similar charges repel so the balloons push away from each other.

Detailed explanation-2: -The presence of the negative charge will induce electron movement in the sphere. Since like charges repel, negative electrons within the metal sphere will be repelled by the negatively charged balloon.

Detailed explanation-3: -A negatively charged balloon will repel electrons and a positively charged balloon will attract electrons.

Detailed explanation-4: -Rubbing the balloon against hair or wool causes electrons to move from the hair or wool to the balloon. Because electrons are negatively charged, the balloon acquires a net negative charge.