The ratio of the amplitude of the electric field to that of the magnetic field `(|E|//|B|)` of an electromagnetic wave travelling in vacume is always

Options

A. equal to 1
B. greater than 1
C. less than 1
D. zero

Explanation

To solve the question regarding the ratio of the amplitude of the electric field to that of the magnetic field in an electromagnetic wave traveling in a vacuum, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Relationship**: In an electromagnetic wave, the electric field (E) and magnetic field (B) are related by the speed of light (c). The relationship can be expressed as:
\[ c = \frac{|E|}{|B|} \]
where \(|E|\) is the amplitude of the electric field and \(|B|\) is the amplitude of the magnetic field.

2. **Rearranging the Equation**: From the above equation, we can rearrange it to find the ratio of the electric field amplitude to the magnetic field amplitude:
\[ \frac{|E|}{|B|} = c \]

3. **Value of c**: The speed of light in a vacuum is approximately \(3 \times 10^8 \, \text{m/s}\). This value is greater than 1.

4. **Conclusion**: Since \(|E|/|B| = c\) and \(c\) is greater than 1, we conclude that the ratio of the amplitude of the electric field to that of the magnetic field in an electromagnetic wave traveling in a vacuum is always greater than 1.

5. **Final Answer**: Therefore, the correct answer is that the ratio \(|E|/|B|\) is always greater than 1.