On decreasing the distance between the plates of a parallel plate capacitor, its capacitance :

Options

A. remains unaffected
B. decreases
C. first increases then decreases
D. increases

Answer

To solve the question regarding the effect of decreasing the distance between the plates of a parallel plate capacitor on its capacitance, we can follow these steps:

### Step 1: Understand the formula for capacitance
The capacitance \( C \) of a parallel plate capacitor is given by the formula:
\[ C = \frac{\varepsilon A}{d} \]
where:
- \( C \) is the capacitance,
- \( \varepsilon \) is the permittivity of the dielectric material between the plates,
- \( A \) is the area of one of the plates,
- \( d \) is the distance between the plates.

### Step 2: Analyze the effect of decreasing distance \( d \)
From the formula, we can see that capacitance \( C \) is inversely proportional to the distance \( d \) between the plates. This means that as \( d \) decreases, the capacitance \( C \) will increase.

### Step 3: Conclusion
Therefore, if the distance \( d \) between the plates is decreased, the capacitance \( C \) will increase.

### Final Answer
The capacitance of a parallel plate capacitor increases when the distance between the plates is decreased.

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