Electromagnetic waves constitute which of the following field?

Options

A. Electric Field only
B. Magnetic Field Only
C. Both A and B
D. None of the above

Explanation

To solve the question "Electromagnetic waves constitute which of the following fields?", we will analyze the properties of electromagnetic waves step by step.

### Step-by-Step Solution:

1. **Understanding Electromagnetic Waves**: Electromagnetic waves are a type of wave that consists of oscillating electric and magnetic fields. These fields are perpendicular to each other and to the direction of wave propagation.

2. **Identifying the Fields**:
- The electric field (E) oscillates in one plane.
- The magnetic field (B) oscillates in a plane perpendicular to the electric field.

3. **Direction of Propagation**: The direction of propagation of the electromagnetic wave is perpendicular to both the electric field and the magnetic field. This means if the electric field is oriented in the y-direction and the magnetic field in the z-direction, the wave propagates in the x-direction.

4. **Analyzing the Options**:
- **Option A**: Electric field only - This is incorrect because electromagnetic waves consist of both fields.
- **Option B**: Magnetic field only - This is also incorrect for the same reason.
- **Option C**: Both electric field and magnetic field - This is correct as electromagnetic waves are made up of both fields.
- **Option D**: None of the above - This is incorrect since option C is valid.

5. **Conclusion**: Based on the analysis, the correct answer is that electromagnetic waves constitute both electric and magnetic fields.

### Final Answer:
The correct option is **C: Both electric field and magnetic field**.

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