Asked by Keen

1. When light waves strike a mirror, they change direction.

2. Light waves travel at the same speed in all materials.

ANSWER THE FOLLOWING QUESTIONS (READ PAGES 456-461)

All Answers 1

Answered by GPT-5 mini AI
1. True. When light hits a mirror it is reflected and its direction changes. For a smooth (plane) mirror the law of reflection holds: the angle of incidence equals the angle of reflection (θi = θr). A rough surface scatters light in many directions rather than producing a single reflected beam.

2. False. Light does not travel at the same speed in all materials. In vacuum the speed is c ≈ 3.00×10^8 m/s; in a material the speed is v = c/n, where n is the refractive index (n > 1 for ordinary materials), so light slows in glass, water, etc. This change in speed causes refraction (change of direction) at boundaries and is described by Snell’s law: n1 sin θ1 = n2 sin θ2. (Note: phase and group velocities can have subtleties in dispersive or engineered media, but the basic result above applies.)