Question

Refractive index of diamond with respect to glass is 1.6 and the absolute refractive index of glass is 1.5. Find out the absolute refractive index of diamonds.
A.) 2.4
B.) 1.6
C.) 1.06
D.) None of the above

Answer 1

Hint: In this question we will use $v = \dfrac{c}{n}$ where the refractive index $n$of a medium is a measure for how much the velocity of light is reduced inside the medium.

Complete step-by-step answer:

Formula used: $v = \dfrac{c}{n}$

According to the question it is given that :

Diamond refractive index with respect to glass ${n_{dg}} = 1.6$
Glass refractive index ${n_g} = 1.5$
Diamond refractive index ${n_d} = ?$

Now, the refractive index of diamond with respect to glass

${n_{dg}} = \dfrac{{{n_d}}}{{{n_g}}}$
So, the refractive index of diamond ${n_d} = {n_{dg}} \times {n_g}$
${n_d} = 1.6 \times 1.5 = 2.4$

Hence, the Diamond refractive index is $2.4$.

Note: In these types of questions we use the definition of absolute refractive index, i.e. a medium in vacuum refractive index. More specifically, it's the ratio of light speed in vacuum to light speed in that medium. This is still bigger than one.