A plane electromagnetic wave travels in vacuum along z- direction. What can you say about the directions of ots electric and magnetic field vectors. If the frequency of the wave is `30 MHz`, what is its wavelength?

Explanation

To solve the question, we will break it down into two parts: determining the directions of the electric and magnetic field vectors, and calculating the wavelength of the electromagnetic wave given its frequency.

### Step 1: Determine the Directions of Electric and Magnetic Fields

1. **Understanding Wave Propagation**: The problem states that the electromagnetic wave is traveling in the z-direction. In electromagnetic waves, the electric field (E) and magnetic field (B) are always perpendicular to each other and also perpendicular to the direction of wave propagation.

2. **Identifying the Plane**: Since the wave is traveling along the z-axis, the electric field vector (E) and the magnetic field vector (B) must lie in the xy-plane. This means that both E and B are oriented in such a way that they do not have any component in the z-direction.

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