The ratio of SI to cgs units of magnetic field is

Options

A. `10 ^(4)`
B. `10^(2)`
C. `10^(-4)`
D. `10^(5)`

Answer

To find the ratio of the SI unit to the CGS unit of magnetic field, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the SI Unit of Magnetic Field**:
The SI unit of magnetic field is the Tesla (T).

2. **Identify the CGS Unit of Magnetic Field**:
The CGS unit of magnetic field is the Gauss (G).

3. **Establish the Relationship Between Tesla and Gauss**:
We know from physics that:
\[ 1 \text{ Tesla} = 10^4 \text{ Gauss} \]
This means that one Tesla is equivalent to 10,000 Gauss.

4. **Set Up the Ratio**:
To find the ratio of the SI unit (Tesla) to the CGS unit (Gauss), we can express it as:
\[ \text{Ratio} = \frac{\text{SI unit}}{\text{CGS unit}} = \frac{1 \text{ Tesla}}{1 \text{ Gauss}} \]

5. **Substitute the Relationship into the Ratio**:
Using the relationship established in step 3, we can substitute:
\[ \text{Ratio} = \frac{10^4 \text{ Gauss}}{1 \text{ Gauss}} \]

6. **Simplify the Ratio**:
The Gauss units will cancel out:
\[ \text{Ratio} = 10^4 \]

7. **Conclusion**:
Therefore, the ratio of the SI unit of magnetic field to the CGS unit of magnetic field is:
\[ \text{Ratio} = 10^4 \]

### Final Answer:
The ratio of SI to CGS units of magnetic field is \(10^4\).

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