Chapter 33

A refracting telescope has the objective lens of focal length $10.0\mathrm{m}$. Assume it is used with an eyepiece of focal length $2.00\mathrm{cm}$. What is the magnification of this telescope?

What is the magnification of a telescope with $f_0=1.00\cdot {10}^2\mathrm{cm}$ and $f_e=5.00\mathrm{cm}?$

Galileo discovered the moons of Jupiter in the fall of $1609.$ He used a telescope of his own design that had an objective lens with a focal length of $f_o=40.0$ inches and an eyepiece lens with a focal length of $f_e=2.00$ inches. Calculate the magnifying power of Galileo's telescope.

Two distant stars are separated by an angle of 35 arcseconds. If you have a refracting telescope whose objective lens focal length is $3.5\mathrm{m}$, what focal length eyepiece do you need in order to observe the stars as though they were separated by 35 arcminutes?

Two refracting telescopes are used to look at craters on the Moon. The objective focal length of both telescopes is $95.0\mathrm{cm}$ and the eyepiece focal length of both telescopes is $3.80\mathrm{cm}.$ The telescopes are identical except for the diameter of the lenses. Telescope A has an objective diameter of $10.0\mathrm{cm}$ while the lenses of telescope $\mathrm{B}$ are scaled up by a factor of two, so that its objective diameter is $20.0\mathrm{cm}$. a) What are the angular magnifications of telescopes $A$ and $B$ ? b) Do the images produced by the telescopes have the same brightness? If not, which is brighter and by how much?

Some reflecting telescope mirrors utilize a rotating tub of mercury to produce a large parabolic surface. If the tub is rotating on its axis with an angular frequency $\omega ,$ show that the focal length of the resulting mirror is: $f=g/2{\omega }^2$.

Suppose the near point of your eye is $2.0\cdot {10}^1\mathrm{cm}$ and the far point is infinity. If you put on -0.20 diopter spec tacles, what will be the range over which you will be able to see objects distinctly?

A classmate claims that by using a $40.0-\mathrm{cm}$ focal length mirror, he can project onto a screen a $10.0-\mathrm{cm}$ tall bird locat ed 100 . $\mathrm{m}$ away. He claims that the image will be no less than $1.00\mathrm{cm}$ tall and inverted. Will he make good on his claim?

An object is $6.0\mathrm{cm}$ from a thin lens along the axis of the lens. If the lens has a focal length of $9.0\mathrm{cm},$ determine the image distance.

You are experimenting with a magnifying glass (consisting of a single converging lens) at a table. You discover that by holding the magnifying glass $92.0\mathrm{mm}$ above your desk, you can form a real image of a light that is directly overhead. If the distance between the light and the table is $2.35\mathrm{m},$ what is the focal length of the lens?