What happens to the capacitance if the separation between the plates of a capacitor decreases?

• A. Capacitance decreases
• B. Capacitance stays the same
• C. Capacitance increases
• D. Capacitance becomes zero

Answer: (C)

Capacitance is defined by the equation ( C = \frac{\varepsilon_0 A}{d} ), where ( C ) is the capacitance, ( \varepsilon_0 ) is the permittivity of free space, ( A ) is the area of the plates, and ( d ) is the separation between the plates. From this equation, it can be observed that capacitance is inversely proportional to the distance ( d ) between the plates. Therefore, when the distance ( d ) decreases, the capacitance ( C ) increases, assuming that the area ( A ) of the plates and the permittivity ( \varepsilon_0 ) remain constant.

As the plates come closer together, the electric field between them strengthens, allowing the capacitor to store more charge at the same voltage. Thus, a decrease in plate separation leads to an increase in capacitance, making it possible to store more electrical energy per volt applied. This principle is crucial in the design of capacitors in various electronic applications, where maximizing capacitance can significantly affect performance.

In summary, reducing the separation between the plates results in an increase in capacitance, allowing for greater charge storage capacity as described by