Voltage of modulating wave of 5 V with 10 MHz frequency was superimposed on carrier wave of frequency 20 MHz and voltage 20 V then the modulation index is

Options

A. `0.25`
B. `1.25`
C. `2.43`
D. `64.0`

Explanation

To find the modulation index (μ) in the given scenario, we will follow these steps:

### Step-by-Step Solution:

1. **Identify the Given Values**:
- Voltage of the modulating wave (Vm) = 5 V
- Voltage of the carrier wave (Vc) = 20 V

2. **Understand the Formula for Modulation Index**:
- The modulation index (μ) is defined as the ratio of the voltage of the modulating wave to the voltage of the carrier wave.
- The formula is given by:
\[ \mu = \frac{V_m}{V_c} \]

3. **Substitute the Values into the Formula**:
- Substitute Vm and Vc into the formula:
\[ \mu = \frac{5 \, \text{V}}{20 \, \text{V}} \]

4. **Calculate the Modulation Index**:
- Perform the division:
\[ \mu = \frac{5}{20} = \frac{1}{4} = 0.25 \]

5. **Conclusion**:
- The modulation index (μ) is 0.25.

### Final Answer:
The modulation index is **0.25**.

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