NumericalModerate2 marks
A boy uses blue colour of light to find the refractive index of glass. He then repeats the experiment using red colour of light. Will the refractive index be the same or different in the two cases? Give a reason to support your answer.
Topic: Electromagnetic spectrum / scattering
Previous-year question practice database
Answer
Exam answer
Different. The refractive index for blue light is greater than for red light.
Explanation
Blue light has a shorter wavelength and travels more slowly in glass.
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