Which statement correctly describes refraction in terms of wave travel?

Which statement correctly describes refraction in terms of wave travel?

• A. Refraction involves the wave changing direction as it passes along the boundary with no speed change
• B. Refraction involves the wave changing direction and speed as it passes into a different medium
• C. Refraction involves the wave stopping at the boundary
• D. Refraction occurs only with sound waves

Answer: (B)

Refraction happens because a wave slows down or speeds up when it enters a different medium. When the boundary is met at an angle, the part of the wave in the new medium changes speed relative to the part still in the old medium. This difference in speeds causes the wavefronts to tilt and the wave to bend in a new direction. The wave continues moving in the new medium, just with a different speed (and wavelength). The wave does not stop at the boundary, and refraction occurs for many kinds of waves, not just sound. So the correct description is that refraction involves the wave changing direction and speed as it passes into a different medium.

Refraction happens because a wave slows down or speeds up when it enters a different medium. When the boundary is met at an angle, the part of the wave in the new medium changes speed relative to the part still in the old medium. This difference in speeds causes the wavefronts to tilt and the wave to bend in a new direction. The wave continues moving in the new medium, just with a different speed (and wavelength). The wave does not stop at the boundary, and refraction occurs for many kinds of waves, not just sound. So the correct description is that refraction involves the wave changing direction and speed as it passes into a different medium.