Question

For a material medium, the values of refractive index for violet and red colours are given as $n_{v}=\text{1.56}$ and $n_{r}=\text{1.44}$ . The dispersive power of a prism made out of this material is

• A. $0.06$
• B. $0.24$
• C. $0.03$
• D. none of these

Answer 1

Answer: (B)

Dispersive power of a prism is given as,
$\omega =\frac{n_{v} - n_{r}}{\left(\right. \frac{n_{v} + n_{r}}{2} \left.\right) - 1}=\frac{\text{1.56} - \text{1.44}}{\left(\right. \frac{\text{1.56} + \text{1.44}}{2} \left.\right) - 1}=\text{0.24}$