Physics for IGCSE & O level - Rays And Waves (Section 11 - No. 13)
What is the approximate speed of all electromagnetic waves?
300,000 km/s
150,000 km/s
100,000 km/s
600,000 km/s
คำอธิบาย
All electromagnetic waves travel at the speed of light (approximately 300,000 km/s).