In lens displacement method lateral magnifications obtained are $2$ and $0.5$. If separation between position of lenses is $30 \mathrm{cm}$, then focal length of the lens is

A thin convex lens of focal length $20 \mathrm{cm}$ is split into parts as shown in figure. An object $O$ is placed at distance $10 \mathrm{cm}$ from the lens. The distance between two virtual images of object will be

Consider the figure shown. What is the amount by which the horizontal ray incident on the prism is deviated after it is reflected from the vertical plane mirror?

A ray of light makes normal incidence on the diagonal face of a right-angled prism as shown in figure. If $\theta =$ $37°$ then the angle of deviation is $\left(\sin 37°=\frac{3}{5}\right)$