The explanation for refraction must involve a change in Warm air you
A. speed.
B. frequency.
C. wavelength.
D. all of these.
The correct answer and explanation is :
Correct Answer: A. Speed.
Explanation:
Refraction is the bending of light as it passes from one medium to another with a different optical density. This bending occurs due to a change in the speed of light in the new medium. When light enters a medium like warm air from a cooler one, its speed changes, which in turn alters its direction.
Light travels at different speeds in different media. In a vacuum, light moves at its maximum speed, about 299,792 kilometers per second. When it moves into a medium such as air, water, or glass, it slows down depending on the medium’s refractive index. Warm air is less dense than cold air, so light travels slightly faster through warm air than cold air. This difference in density and speed causes light rays to bend—this bending is what we call refraction.
The frequency of light remains constant during refraction. This is because frequency is determined by the source of the light and does not change when the light moves from one medium to another. However, since the speed of light changes and the frequency stays the same, the wavelength of light must also change to satisfy the wave equation:
[
\text{Speed} = \text{Frequency} \times \text{Wavelength}
]
While both the wavelength and speed of light change during refraction, the fundamental cause of refraction is the change in speed, making option A the most accurate answer.
Option D (“all of these”) might seem tempting, but since the frequency doesn’t change during refraction, it’s not correct. The primary explanation must focus on speed, as that’s what directly causes the bending of light at the boundary between two media.