Lakhmir Singh and Manjit Kaur Solutions for Chapter: Refraction of Light, Exercise 27: Short Answer Type Questions

A concave lens of focal length $15 \mathrm{cm}$ forms an image $10 \mathrm{cm}$ from the lens. How far is the object placed from the lens? Draw the ray-diagram.

An object $60 \mathrm{cm}$ from a lens gives a virtual image at a distance of $20 \mathrm{cm}$ in front of the lens. What is the focal length of the lens? Is the lens converging or diverging? Give reasons for your answer.

A concave lens of $20 \mathrm{cm}$ focal length forms an image $15 \mathrm{cm}$ from the lens. Compute the object distance.

A concave lens has focal length $15 \mathrm{cm}$. At what distance should the object from the lens be placed so that it forms an image at $10 \mathrm{cm}$ from the lens? Also find the magnification produced by the lens.

Calculate the image distance for an object of height $12 \mathrm{mm}$ at a distance of $0.20 \mathrm{m}$ from a concave lens of focal length $0.30 \mathrm{m}$, and state the nature and size of the image.

A concave lens has a focal length of $20 \mathrm{cm}$. At what distance from the lens a $5 \mathrm{cm}$ tall object be placed so that it forms an image at $15 \mathrm{cm}$ from the lens? Also calculate the size of the image formed.

An object is placed $20 \mathrm{cm}$ from (a) a converging lens, and (b) a diverging lens, of focal length $15 \mathrm{cm}$. Calculate the image position and magnification in each case.

A $2.0 \mathrm{cm}$ tall object is placed $40 \mathrm{cm}$ from a diverging lens of focal length $15 \mathrm{cm}$. Find the position and size of the image.