The ratio of the emu of charge to esu of charge is :

Options

A. `3xx10^(10)`
B. `4.8xx10^(-19)`
C. `1//10`
D. `1//300`

Answer

To solve the question regarding the ratio of the electromagnetic unit (EMU) of charge to the electrostatic unit (ESU) of charge, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Units**:
- EMU (Electromagnetic Unit) is also known as Abkulam.
- ESU (Electrostatic Unit) is used for measuring electric charge in static conditions.

2. **Know the Relationship**:
- We need to find the ratio of EMU to ESU.
- We know that 1 Coulomb (C) of charge can be expressed in terms of both EMU and ESU.

3. **Coulomb to ESU and EMU Conversion**:
- From the information provided, we have:
- 1 Coulomb = \(3 \times 10^9\) ESU
- 1 Coulomb = \(1 \times 10\) EMU

4. **Set Up the Ratio**:
- We want to find the ratio \( \frac{EMU}{ESU} \).
- Using the conversions:
\[ \frac{EMU}{ESU} = \frac{1 \times 10 \text{ EMU}}{3 \times 10^9 \text{ ESU}} \]

5. **Calculate the Ratio**:
- Simplifying the ratio:
\[ \frac{1 \times 10}{3 \times 10^9} = \frac{1}{3} \times 10^{-8} = \frac{1}{3} \times 10^{10} \]
- Therefore, we can express this as:
\[ \frac{EMU}{ESU} = 3 \times 10^{10} \]

6. **Final Answer**:
- The ratio of EMU of charge to ESU of charge is \(3 \times 10^{10}\).

### Conclusion:
The correct answer is option A: \(3 \times 10^{10}\).