As the colour of light varies from red to violet, the refractive index of a certain material changes by 0.014 . A rectangular slab of height 2.00 cm constructed from this material is placed over a newspaper. When observed normally in yellow light, the letters appear to be 1.32 cm below the top surface of the slab. Determine the dispersive power of the material.

Step-by-step solution

The refractive index for yellow light is given by _y = Real depth Apparent depth . Substituting the given values: _y = 2.00 1.32 = 50 33 The dispersive power is given by the formula: = _v - _r _y - 1 Given that the change in refractive index from red to violet is _v - _r = 0.014 . Substituting the values into the formula for dispersive power: = 0.014 50 33 - 1 = 0.014 17 33 = 0.014 33 17 = 0.462 17 0.027