Question

Assertion- The light of violet colour deviates the most and the light of red colour the least, while

passing through the prism. (1)

Reason- For a prism material, Refractive index is the highest for red light and the lowest for violet

colour​

Answer 1

Answer:

Assertion is true but reason is false.

Explanation:

The light for which prism has greater refractive index deviates or bends the most. We observe that violet deviates the most, but red deviates the least.

So, the refractive index is greatest for violet and least for red.

Answer 2

Assertion is true but reason is false.

Explanation:

• Refractive index is the ratio of speed of light in vacuum to the speed of light in a medium.

• η$=\frac{c}{v}$ where c is the speed of light in vacuum and v is the speed of light in the medium.

• Refractive index for red light in prism = 1.52

• Refractive index for violet light in prism = 1.54

• Refractive index of glass for red light is less than than for violet light.

• This is the reason that speed of red is more than violet light because refractive index is inversely proportional to speed of light in that medium.

• And this is why red light bends less than violet light when entering prism.
• Violet light bends the most while undergoing dispersion.