Kumar Mittal Solutions for Exercise 1: QUESTIONS

An astronomical telescope consists of two convex lenses having focal length $80 \mathrm{cm}$ and $4 \mathrm{cm}$. When it is in normal adjustment, What is its length?

An astronomical telescope consists of two convex lenses having focal length $80 \mathrm{cm}$ and $4 \mathrm{cm}$. When it is in normal adjustment, What is its magnifying power?

What will be the maximum length of a telescope formed by lenses of focal lengths $4.0 \mathrm{cm}$ and $60 \mathrm{cm}$? What will be the magnifying power? Is it also maximum?

An astronomical telescope having a magnifying power of $6$ for relaxed eye consists of two thin lenses $35 \mathrm{cm}$ apart. Find the focal lengths of the lenses.

The focal length of the objective of an astronomical telescope is $1.0 \mathrm{m}$. If the magnifying power of telescope is $20$, then determine the focal length of the eye-piece and the length of the telescope for relaxed eye.

A telescope objective has a focal length $1.00 \mathrm{m}$. When the final image is formed at the least distance of distinct vision ($25 \mathrm{cm}$), the distance between the lenses is $1.05 \mathrm{m}$. Calculate the focal length of the eyepiece and the magnifying power of the telescope.

The objective of a telescope focussed for the least distance of distinct vision forms the image $0.75 \mathrm{m}$ behind it. The distance between the two lenses is $0.80 \mathrm{m}$. What is the magnifying power of the telescope? For seeing with relaxed eye, by how much distance will the eye-piece have to be moved back? What will be the magnifying power then?

An astronomical telescope has an objective of focal length $200 \mathrm{cm}$ and an eye-piece of focal length $10 \mathrm{cm}$. An observer adjusts the distance of the eyepiece from the objective to obtain the image of the sun on a screen $40 \mathrm{cm}$ behind the eye-piece. The diameter of the sun’s image is $6.0 \mathrm{cm}$. Find the diameter of the sun. The average earth-sun distance is $1.5\times {10}^{11}\mathrm{m}$.