What is refraction?

What is refraction?

• A. Bending of waves as they pass from one medium to another, due to a change in their speed
• B. Absorption of waves by objects
• C. Scattering of waves in multiple directions
• D. Doppler shift of waves due to motion

Answer: (A)

Refraction is the bending of waves as they pass from one medium to another because their speed changes. When a wave hits the boundary at an angle, part of it enters the new medium and slows down (or speeds up) before the rest, causing the wavefront to tilt and the path to bend. If the new medium is denser for that wave, it slows down and bends toward the normal; if it’s less dense for that wave, it speeds up and bends away from the normal. A familiar example is light refracting when it enters water or a glass prism, which can also lead to color separation in white light. This is different from absorption (energy diminishes as waves are taken up by the medium), scattering (waves spread in multiple directions), or the Doppler shift (a change in observed frequency due to motion). Refraction is about a change in direction caused by a change in speed at the boundary.

Refraction is the bending of waves as they pass from one medium to another because their speed changes. When a wave hits the boundary at an angle, part of it enters the new medium and slows down (or speeds up) before the rest, causing the wavefront to tilt and the path to bend. If the new medium is denser for that wave, it slows down and bends toward the normal; if it’s less dense for that wave, it speeds up and bends away from the normal. A familiar example is light refracting when it enters water or a glass prism, which can also lead to color separation in white light. This is different from absorption (energy diminishes as waves are taken up by the medium), scattering (waves spread in multiple directions), or the Doppler shift (a change in observed frequency due to motion). Refraction is about a change in direction caused by a change in speed at the boundary.