The capacity of parllel plate condenser depends on

Options

A. The speration between the plates
B. The potential applied across the plates
C. The amount of charge
D. Both (2) and (3)

Answer

To determine the factors on which the capacity (capacitance) of a parallel plate capacitor depends, we can analyze the situation step by step.

### Step 1: Understanding Capacitance
Capacitance (C) is defined as the ability of a capacitor to store charge per unit voltage. The formula for the capacitance of a parallel plate capacitor is given by:

\[ C = \frac{\varepsilon_0 A}{d} \]

where:
- \(C\) is the capacitance,
- \(\varepsilon_0\) is the permittivity of free space (a constant),
- \(A\) is the area of one of the plates, and
- \(d\) is the distance between the plates.

### Step 2: Analyzing the Formula
From the formula, we can see that:
- The capacitance \(C\) is directly proportional to the area \(A\) of the plates. This means that if the area increases, the capacitance increases.
- The capacitance \(C\) is inversely proportional to the distance \(d\) between the plates. This means that if the distance increases, the capacitance decreases.

### Step 3: Evaluating the Options
Now, let's evaluate the options provided in the question:

1. **The separation between the plates**: This directly affects the capacitance as seen from the formula. Increasing the separation decreases the capacitance. **(True)**

2. **The potential applied across the plates**: The capacitance itself does not depend on the potential difference; it is a property of the capacitor determined by the physical characteristics (area and distance). **(False)**

3. **The amount of charge**: While the charge stored in the capacitor is related to the capacitance and the voltage (Q = CV), the capacitance itself does not depend on the amount of charge. **(False)**

4. **Both second and third**: Since both options 2 and 3 are false, this option is also false. **(False)**

### Conclusion
Based on the analysis, the capacity of a parallel plate capacitor depends on the separation between the plates and the area of the plates. Therefore, the correct answer is that the capacitance depends on the separation between the plates.

### Final Answer
The capacity of a parallel plate capacitor depends on the separation between the plates (option 1).

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