Peak value of magnetic field is 20 nT for an electromagnetic wave . What will be the peak value of electric intensity in SI units ?

Explanation

To find the peak value of electric field intensity (E₀) given the peak value of magnetic field (B₀) in an electromagnetic wave, we can use the relationship between the electric field and magnetic field in electromagnetic waves, which is given by the equation:

\[ E_0 = B_0 \cdot c \]

Where:
- \( E_0 \) is the peak value of the electric field intensity (in volts per meter, V/m),
- \( B_0 \) is the peak value of the magnetic field (in tesla, T),
- \( c \) is the speed of light in vacuum (approximately \( 3 \times 10^8 \) meters per second).

### Step-by-Step Solution:

1. **Identify the given values:**
- Peak value of magnetic field, \( B_0 = 20 \, \text{nT} = 20 \times 10^{-9} \, \text{T} \)
- Speed of light, \( c = 3 \times 10^8 \, \text{m/s} \)

2. **Use the formula to find \( E_0 \):**
\[ E_0 = B_0 \cdot c \]

3. **Substitute the values into the equation:**
\[ E_0 = (20 \times 10^{-9} \, \text{T}) \cdot (3 \times 10^8 \, \text{m/s}) \]

4. **Perform the multiplication:**
\[ E_0 = 60 \times 10^{-1} \, \text{V/m} \]

5. **Convert to standard form:**
\[ E_0 = 6 \, \text{V/m} \]

### Final Answer:
The peak value of electric field intensity is \( 6 \, \text{V/m} \).