Question

Indicate the colour of light which travels through glass with the minimum speed :

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

Answer 1

The correct option is B Violet

Frequency does not change on change of medium.

$v=f\lambda$

$f$ is constant, $⟹v\propto \lambda$

Violet colour has shortest wavelength and hence it travels through glass with the minimum speed.