Embibe Experts Solutions for Chapter: Ray Optics and Optical Instruments, Exercise 1: Jharkhand Board-2020

On which principle does optical fibre act?

In an astronomical telescope focal lengths of the two lenses are $0.3 \mathrm{m}$ and $0.05 \mathrm{m}$. In normal adjustment the distance between them is.

A $4.5 \mathrm{cm}$ needle is placed $12 \mathrm{cm}$ away from a convex mirror of focal length $15 \mathrm{cm}$. Give the location of the image and determine the magnification.

What is angle of minimum deviation? For refraction of light through a prism, establish the relation $\mu =\frac{\sin \left({\displaystyle \frac{A+{\delta }_m}{2}}\right)}{\sin \left({\displaystyle \frac{A}{2}}\right)}$; Where terms have usual meanings.

If the refractive indices of water and glass are $\raisebox{1ex}{$4$}\!\left/ \!\raisebox{-1ex}{$3$}\right.$ and $\raisebox{1ex}{$3$}\!\left/ \!\raisebox{-1ex}{$2$}\right.$ respectively. The refractive index of glass with respect to water is

If the focal length of objective lens of an astronomical telescope is $20 \mathrm{cm}$ and the length of it is $25 \mathrm{cm}$, the`magnification of the telescope for normal adjustment is.

An object is placed at a distance of $60 \mathrm{cm}$ from a concave lens of focal length $15 \mathrm{cm}$, Determine the magnification of the lens.

Derive the lens maker's formula for a thin lens:

$\frac{1}{f}=\left(\mu -1\right)\left(\frac{1}{R_1}-\frac{1}{R_2}\right)$