Which term describes the bending of a wave as it passes from one medium into another?

Which term describes the bending of a wave as it passes from one medium into another?

• A. Absorption
• B. Reflection
• C. Diffraction
• D. Refraction

Answer: (D)

Refraction is the bending of a wave as it passes from one medium into another. When the wave crosses the boundary, its speed changes because the two media carry the wave at different speeds. That change in speed causes the wave to change direction, so its path is bent at the boundary. For light, this means it can bend toward or away from the normal depending on whether it slows down or speeds up in the new medium. The frequency stays the same, but the wavelength changes, and the amount of bending is described by Snell’s law (n1 sin theta1 = n2 sin theta2). A common everyday example is a straw in a glass of water appearing bent. Absorption would mean the wave loses energy in the medium, reflection is bouncing off the boundary, and diffraction is bending around obstacles or through openings—none of those describe the change in direction that happens when crossing into a different medium.

Refraction is the bending of a wave as it passes from one medium into another. When the wave crosses the boundary, its speed changes because the two media carry the wave at different speeds. That change in speed causes the wave to change direction, so its path is bent at the boundary. For light, this means it can bend toward or away from the normal depending on whether it slows down or speeds up in the new medium. The frequency stays the same, but the wavelength changes, and the amount of bending is described by Snell’s law (n1 sin theta1 = n2 sin theta2). A common everyday example is a straw in a glass of water appearing bent. Absorption would mean the wave loses energy in the medium, reflection is bouncing off the boundary, and diffraction is bending around obstacles or through openings—none of those describe the change in direction that happens when crossing into a different medium.