Problem

- Light from a sodium lamp (

\lambda_0 = 589 \text{ nm}

) passes through a tank of glycerin (refractive index = 1.47) 20 m long in a time

t_1

. If it takes a time

t_2

to transverse the same tank when filled with carbon disulfide (index = 1.63), determine the difference

t_2 - t_1