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Which statement below is incorrect regarding the characteristics of electromagnetic waves?

1. The electric and magnetic field vectors reach their maximum and minimum values at the same position and at the same instant.
2. The energy carried by an electromagnetic wave is shared equally by the electric and magnetic fields.
3. The electric and magnetic field vectors are parallel to each other and both are perpendicular to the direction in which the wave travels.
4. Electromagnetic waves can propagate without needing any material medium.

Correct answer: The electric and magnetic field vectors are parallel to each other and both are perpendicular to the direction in which the wave travels.

Solution

In an electromagnetic wave the electric and magnetic field vectors are perpendicular to each other and to the direction of propagation. The statement that they are parallel is the incorrect one.

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