If the angle of a prism is $60^{\circ}$ and the angle of minimum deviation is $40^{\circ}$,then the angle of refraction will be (in $^{\circ}$)

$A$ thin prism of angle $5^{\circ}$ is placed at a distance of $10\,cm$ from an object. What is the distance of the image from the object? (Given refractive index $\mu$ of prism $= 1.5$)

$A$ thin prism of angle $6^{\circ}$ made of glass of refractive index $1.5$ is combined with another prism made of glass of refractive index $1.75$ to produce dispersion without deviation. Then, the angle of the second prism is (in $^{\circ}$)

When a glass prism of refracting angle $60^{\circ}$ is immersed in a liquid, its angle of minimum deviation is $30^{\circ}$. The critical angle of glass with respect to the liquid medium is (in $^{\circ}$)

If $r_1$ and $r_2$ are the angles of refraction at the first and second faces of a prism,respectively,then the angle of the prism is:

$A$ ray of light passing through a prism $(\mu = \sqrt{3})$ suffers minimum deviation. It is found that the angle of incidence is double the angle of refraction within the prism. Then,the angle of prism is ..... (in degrees).