Question

When a beam of white light falls on the surface of a triangular prism of glass, it splits, after emerging out from the prism, into various colours with different deviations. Which colour has maximum deviation?

• A. Red
• B. Yellow
• C. Green
• D. Violet

Hint:

In a prism, violet light deviates the most due to its shorter wavelength, while red light, with its longer wavelength, deviates the least.

Answer 1

The Correct Option is D

Step 1: Understand the dispersion of light.
When white light passes through a prism, it undergoes dispersion, separating into its constituent colours. These colours have different wavelengths and therefore different refractive indices in the material of the prism.
Step 2: Relationship between wavelength and deviation.
The amount of deviation of light depends on its wavelength. Light with shorter wavelengths (like violet) deviates more than light with longer wavelengths (like red).
Step 3: Conclusion.
Therefore, the colour with the maximum deviation is violet. The correct answer is (D).