Period is measured in seconds. All waves, including sound waves and electromagnetic waves, follow this equation. It should be noted that some particular waves have their own specific speeds ...

He knew that physicists now believed light waves--usually thought of as a constantly fluctuating electromagnetic wave ... this mathematically into a set of equations. These--known, not ...

the speed of light and all electromagnetic waves in a vacuum is 300,000,000 m/s or 3×10 8 m/s the speed of sound in air is often taken to be 340 m/s.