Question

If the voltage across a capacitor is doubled:

a. the capacitance is doubled
b. the amount of charge stored is halved
c. the capacitance decreases by one fourth
d. the capacitance remains the same

Answer 1

The capacitance of a capacitor remains the same when the voltage across it is doubled; only the stored charge and energy are affected, both of which would double with a doubling of voltage.

Step-by-step explanation:

If the voltage across a capacitor is doubled, then the correct answer is that the capacitance remains the same. This is because capacitance is a measure of a capacitor's ability to store charge per unit voltage and is defined by the formula C = Q/V, where C is the capacitance, Q is the charge, and V is the voltage. When you double the voltage across a capacitor and the capacitance remains constant, the charge stored in the capacitor also doubles because charge is directly proportional to voltage, Q = C*V. Therefore, if the voltage is doubled, the stored charge and the stored energy in the capacitor will both double, not the capacitance itself.