Physics
A light ray passes from water to (i) air, and (ii) glass. In each case, state how does the speed of light change?
Answer
As we know,
Refractive index of air, μa = 1.0003
Refractive index of water, μw = 1.33
Refractive index of ordinary glass, μg = 1.5
With the help of the above values, we can see that μg > μw > μa
When a ray of light gets refracted from a rarer to a denser medium, the speed of light decreases, while if it is refracted from a denser to a rarer medium, the speed of light increases.
So on the basis of above information, we can say that —
(i) When a ray of light passes from water to air, its speed increases as it is moving from a denser to a rarer medium.
(ii) When a ray of light passes from water to glass, its speed decreases as it is moving from a rarer to a denser medium.
Related Questions
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