Both mechanical waves and EM waves interact with a change in what?

Answer 1

All waves move energy, not matter. All waves are created by vibrations. Mechanical waves are caused by vibrating matter such as vocal chords or a drum. EM waves are created by vibrating electrons in atoms that propogate through the electric and magnetic fields that exist everywhere in the universe. All waves can reflect, refract. and diffract. This is where the similarities end. Both types of waves interact with matter and experience a change in velocity but do not interact with each other. Mechanical waves require matter as a medium through which to travel, they don't travel through a vacum. EM waves travel best through a vacum and lose energy as they move into more dense matter. All waves refract when they change velocity as they move from one medium into another, like air into water. Remember, there are some similarities amongst all types of waves, EM, mechanical, surface, and siesmic, but their behaviors are quite varied and complex.