Embibe Experts Solutions for Chapter: Ray Optics, Exercise 1: TS EAMCET - 5 August 2021 Shift 1

An object is placed in front of a spherical concave mirror between the focal point and the radius of curvature. Its image is

Blue light travelling in a vacuum has a wavelength of $450 \mathrm{nm}.$ It enters a medium whose refractive index is $1.5.$ What is its frequency in the medium?
(Speed of light in vacuum $=3\times {10}^8 \mathrm{m} {\mathrm{s}}^{-1}$)

Where should an object be placed on the axis of a convex lens of focal length $8 \mathrm{cm}$ so as to achieve magnification of $-4$? (Distances are measured from optic centre of the lens)

A converging mirror is placed on the right hand side of a converging lens as shown in the figure. The focal length of the mirror and the lens are $20 \mathrm{cm}$ and $15 \mathrm{cm}$ respectively. The separation between the lens and the mirror is $40 \mathrm{cm}$ and their principal axes coincide. A point source is placed on the principal axis at a distance $d$ to the left of the lens. If the final beam comes out parallel to the principal axis, then the value of $d$ is:

Three lenses of focal lengths $+10 \mathrm{cm},-10 \mathrm{cm}$ and $+30 \mathrm{cm}$ are placed at a distance of $30 \mathrm{cm},35 \mathrm{cm}$ and $45 \mathrm{cm}$ respectively from an object. The distance between the object and the image formed is

A screen is placed $90 \mathrm{cm}$ from an object. The image is formed by using a convex lens twice on the screen by putting the lens at two different locations separated by $20 \mathrm{cm}.$ The focal length of the lens is approximately equal to:

A point source is located at a distance of $20 \mathrm{cm}$ from the front surface of a symmetrical glass biconvex lens with equal radii of curvature $5 \mathrm{cm}.$ The distance at which image formed from the rear surface of this lens is [Given refractive index of the glass is $1.5$]

Two lenses of power $-1.6$ D and $+2.1$ D respectively are placed in contact. The focal length of the combination is