Choose the correct relation:

Options

A. `q=V//C`
B. `C=Vxxq`
C. `V=q//c`
D. `V=cq`

Explanation

To solve the problem, we need to identify the correct relation among the given options related to a capacitor. The relevant quantities are charge (q), potential difference (v), and capacitance (c).

### Step-by-Step Solution:

1. **Understand the Definitions**:
- **Charge (q)**: The amount of electric charge stored in the capacitor.
- **Potential Difference (v)**: The voltage across the capacitor.
- **Capacitance (c)**: The ability of a capacitor to store charge per unit voltage, defined as \( c = \frac{q}{v} \).

2. **Recall the Fundamental Relation**:
- The fundamental relation that connects these three quantities is given by:
\[ q = cv \]
- This means that the charge (q) stored in a capacitor is equal to the capacitance (c) multiplied by the potential difference (v).

3. **Rearranging the Equation**:
- From the relation \( q = cv \), we can rearrange it to express potential difference (v) in terms of charge (q) and capacitance (c):
\[ v = \frac{q}{c} \]
- This shows that the potential difference is directly proportional to the charge and inversely proportional to the capacitance.

4. **Analyzing the Given Options**:
- Now, let's analyze the provided options:
- Option 1: \( q = \frac{v}{c} \) (Incorrect)
- Option 2: \( c = vq \) (Incorrect)
- Option 3: \( v = \frac{q}{c} \) (Correct)
- Option 4: \( v = cq \) (Incorrect)

5. **Conclusion**:
- The correct relation among the given options is:
\[ v = \frac{q}{c} \]
- Therefore, the correct option is **Option 3**.