Question

Which of the following is a true statement? A. Electromagnetic waves consist of only changing electric fields B. Electromagnetic waves can Darien speed, wavelength and frequency C. Electromagnetic waves do not always need a medium to travel D. Electromagnetic waves are longitudinal waves

Answer 1

C. Electromagnetic waves do not always need a medium to travel.

Electromagnetic waves differ from mechanical waves because they do not require a medium to travel. This means that electromagnetic waves can travel not only through air and solid materials, but also through the vacuum of space. Also, they are transverse so they do not need a medium material. For an electromagnetic wave to be admitted, there must be an acceleration of an electric charge.

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