Question

Which are characteristics of a ray when it hits a boundary and reflects, but not when it hits the boundary and refracts? Check all that apply.

changes direction
changes speed
does not change direction
does not change speed
bounces off the boundary
passes through the bound

Answer 1

- does not change speed
- bounces off the boundary

Reason: On reflection the ray stays in the same medium and simply bounces, so its speed in the medium is unchanged. Refraction involves passing into a different medium and usually changing speed (and therefore direction), so those do not uniquely describe reflection.