The velocity of electromagnetic waves is
- A3 × 10⁸ ms⁻¹
- B3 × 10⁷ ms⁻¹
- C3 × 10⁶ ms⁻¹
- D3 × 10⁵ ms⁻¹
- ENone of the above/More than one of the above
Show answer and explanation
Correct answer: (a) 3 × 10⁸ ms⁻¹
Explanation
Electromagnetic waves need no medium and travel through vacuum at a constant speed of light.
This velocity is 3 × 10⁸ m s⁻¹, the same for all EM waves (radio, X-rays, gamma rays, visible light).
They consist of mutually perpendicular oscillating electric and magnetic fields.