Question

Comment on the speed of light before it enters the glass, in the glass, and when it exits the glass.

a) Increases, slows down, increases
b) Slows down, increases, slows down
c) Increases, remains constant, increases
d) Slows down, remains constant, slows down

Answer 1

The speed of light slows down when it enters the glass, remains constant while within the glass, and then increases back to its original speed in the air when it exits the glass.

Step-by-step explanation:

When we consider the speed of light as it travels through different mediums, such as air and glass, we observe changes due to the optical density of the material. Initially, before light enters the glass, it travels at its maximum speed in a vacuum, which is approximately 299,792 kilometers per second. Upon entering a denser medium like glass, the light slows down and its wavelength also decreases in that medium due to the higher refractive index of glass compared to air.

While in the glass, the speed of light remains constant but is slower compared to when it is in a vacuum or air. Upon exiting the glass and re-entering a less dense medium like air, the speed of light increases back to its speed in air. Therefore, the correct sequence describing the speed of light at different stages is: slows down, remains constant, slows down.