For the same angle of incidence in media P,Q and R, the angles of refraction are `35^@, 25^@,15^@` respectively. In which medium will the velocity of light be minimum?

Explanation

For Snell's Law `n=(sin i)/(sin r)=(C )/(v)`
For given I, v `alpha` sin r, r is minimum in medium A, so velocity of light is minimum in medium A.