Explain how Corpuscular theory predicts the speed of light in a medium, say, water, to be greater than the speed of light in vacuum. Is the prediction confirmed by experimental determination of the speed of light in water ? If not, which alternative picture of light is consistent with experiment?

Explanation

No, Wave theory
Newton's corpuscular theory of light sates that when light corpuscles the interface of two media from a rarer (air) to denser (water ) medium, the particles experience forces of attraction to the surface. Hence, the normal component of velocity increases while the component along the surface reamins unchanged.
Hence, we can write the expression :
`c sin i= v sin r ....(i)`
i = Angle of incidence
r= Angle of reflection
c= Velocity of light in air
v= Velocity of light in water
We have the relation for relative refractive index of water with respect to air as :
`mu=(v)/(c)`
Hence, equation (i) reduces to
`(v)/(c)=(sin i)/(sinr)=mu " " ....(ii)`
But `mu gt 1`
Hence, it can be inferred from equation (ii) `vgtc`. This is not possible since this prediction is opposite to the experimental results of `c gt v`
The wave picture of light is conistent with the experimental results.