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A small sphere carrying a positive charge is held near a second small sphere carrying a negative charge. What happens between the two spheres?
AThey repel each other, since their charges are alike
BThey attract each other, since their charges are unlike
CThey neither attract nor repel, since both are charged
DThey repel each other, since their charges are unlike
Answer & Solution
Correct answer: B. They attract each other, since their charges are unlike
1. Electric charge comes in two kinds, positive and negative.
2. Charges with the same sign push each other apart, and charges with opposite signs pull toward each other.
3. Here one sphere is positive and the other negative, so the charges are unlike and the spheres attract.
4. Options A and D both claim repulsion, which only happens between like charges, so both are wrong; option C ignores that any nonzero charge produces a force on another charge.
_Source: OpenStax Physics (CC BY 4.0), Ch 18 "Static Electricity", section Electric Charge_
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