How do waves travel?

Answer by  kevincai96 (669)

Waves travel in a straight line (assuming there are no obstacles) and forever (disregarding friction). Mechanical waves, if on Earth, will lose power as they move, because of friction. EM Waves can travel through vacuums and go on forever.

Answer by  john11 (617)

EM waves travel by mutual re-enforcement. When the electrical field changes, the magnetic field varies in time and space, and vice-versa. EM waves travel at C in a vacuum.