Question

A concave refractive surface of a medium having refractive index $\mu$ produces a real image of an object (located outside the medium) irrespective of its location. Choose the correct option from the following

• A. Always
• B. May be if refractive index of surrounding medium is greater than $\mu$
• C. May be if refractive index of surrounding medium is less than $\mu$
• D. None of the above

Answer 1

The correct option is C May be if refractive index of surrounding medium is less than $\mu$

$R=-R$ ; $u=-u$ then , $v<0$

$\frac{{\mu }_2}{v}-\frac{{\mu }_1}{u}=\frac{{\mu }_2-{\mu }_1}{R}$

$\frac{1}{V}=\frac{\mu -1}{-R}+\frac{1}{-u}$

for $\mu >1$ i.e, greater than outside medium then it would always form a real image

option $C$ is correct