In an LCR. series circuit the resonating frequency can be decreased by -

Options

A. Decreasing the value of C
B. Decreasing the value of L
C. Decreasing both the values of L and C
D. Increasing the value of C

Answer

To solve the question regarding how to decrease the resonating frequency in an LCR series circuit, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Resonating Frequency Formula:**
The resonating frequency \( f \) in an LCR series circuit is given by the formula:
\[ f = \frac{1}{2\pi\sqrt{LC}} \]
where \( L \) is the inductance and \( C \) is the capacitance.

2. **Analyze the Relationship:**
From the formula, we can see that the resonating frequency \( f \) is inversely proportional to the square root of the product of \( L \) and \( C \). This means:
\[ f \propto \frac{1}{\sqrt{LC}} \]

3. **Determine How to Decrease Frequency:**
To decrease the resonating frequency \( f \), we need to increase the value of either \( L \) (inductance) or \( C \) (capacitance) or both. This is because increasing \( L \) or \( C \) will increase the denominator in the formula, thereby decreasing the frequency.

4. **Conclusion:**
Therefore, the resonating frequency can be decreased by increasing the values of \( L \) and/or \( C \).

### Final Answer:
The resonating frequency in an LCR series circuit can be decreased by **increasing the values of inductance \( L \) and/or capacitance \( C \)**.

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