alleryStart learning →If the distance between the plates of a capacitor is doubled while the plate area and everything else stays fixed, how does the capacitance change?
AIt quadruples instead
BNothing changes at all
CIt is cut in half
DIt doubles instead
Answer & Solution
Correct answer: C. It is cut in half
1. Capacitance for a parallel-plate capacitor is C = epsilon_0 A / d, which is inversely proportional to the plate separation d.
2. Doubling d divides C by 2.
3. So the capacitance is cut in half, not increased, which is the trap for anyone assuming more separation stores more charge.
_Source: OpenStax Physics (CC BY 4.0), Ch 18 "Static Electricity", section 18.5 Capacitors and Dielectrics_
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