A diffraction-limited lens can focus light to a 10diameter spot on a screen. Do the following actions make the spot diameter larger, make it smaller, or leave it unchanged?
A. Decreasing the wavelength of the light.
B. Decreasing the lens diameter.
C. Decreasing the lens focal length.
D. Decreasing the lens-to-screen distance.
Decreasing the wavelength of the light.
since ,hence from this dependence we have
Decreasing the lens diameter
we know that
Therefore, Decreasing D increases
Decreasing the lens focal length.
Therefore, Decreasing the focal length f will decreases
Decreasing the lens-to-screen distance.
we know that
Decreasing the lens-to-screen distance means the screen is farther from the focal plane. This mean spot will get larger.
Marooned on a desert island and with a lot of time on your hands, you decide to disassemble your glasses to make a crude telescope with which you can scan the horizon for rescuers. Luckily you’re farsighted, and, like most people, your two eyes have different lens prescriptions. Your left eye uses a lens of power and your right eye’s lens is . a. Which lens should you use for the objective and which for the eyepiece? Explain.
b. What will be the magnification of your telescope?
c. How far apart should the two lenses be when you focus on distant objects?
Alpha Centauri, the nearest star to our solar system is light years away. assume that alpha centauri has a planet with an advanced civilization. professor Dhg, at the planet's Astronomical Institute, wants to build a telescope with which he can find out whether any planets are orbiting our sun.
(a). What is the minimum diameter for an objectives lens that will just barely resolve Jupiter and the sun? The radius of Jupiter's orbit is Assume
(b). Building a telescope of the necessary size does not appear to be a major problem. What practical difficulties might prevent professor Dhg's experiment from succeeding?
A common optical instrument in a laser laboratory is a beam expander. One type of beam expander is shown in FIGURE P . The parallel rays of a laser beam of width w1 enter from the left.
a. For what lens spacing d does a parallel laser beam exit from the right?
b. What is the width w2 of the exiting laser beam?
Your task in physics laboratory is to make a microscope from two lenses. One lens has a focal length of 2.0 cm, the other 1.0 cm. You plan to use the more powerful lens as the objective, and you want the eyepiece to be 16 cm from the objective.
a. For viewing with a relaxed eye, how far should the sample be from the objective lens?
b. What is the magnification of your microscope?
94% of StudySmarter users get better grades.Sign up for free