What oscillates in electromagnetic waves ?

Answer

To answer the question "What oscillates in electromagnetic waves?", we can break down the solution into the following steps:

### Step-by-Step Solution:

1. **Understanding Electromagnetic Waves**:
- Electromagnetic waves (EM waves) are a type of wave that can travel through a vacuum or a medium. They are generated by the oscillation of electric charges.

2. **Nature of EM Waves**:
- EM waves are classified as transverse waves. This means that the oscillations of the fields are perpendicular to the direction of wave propagation.

3. **Components of EM Waves**:
- According to Maxwell's equations, EM waves consist of two main components: the electric field (E) and the magnetic field (B).
- Both of these fields oscillate.

4. **Direction of Oscillation**:
- In an electromagnetic wave, the electric field oscillates in one plane, while the magnetic field oscillates in a plane perpendicular to the electric field.
- The direction of propagation of the wave is perpendicular to both the electric and magnetic fields.

5. **Conclusion**:
- Therefore, in electromagnetic waves, it is the electric field and the magnetic field that oscillate.

### Final Answer:
In electromagnetic waves, both the electric field and the magnetic field oscillate.

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