At what speed do electromagnetic waves travel through a vacuum?
- A$300\ \text{m s}^{-1}$
- B$300\ \text{km s}^{-1}$
- C$300\,000\ \text{km s}^{-1}$
- D$300\,000\,000\ \text{km s}^{-1}$
Physics 0625 · IGCSE · Light
At what speed do electromagnetic waves travel through a vacuum?