PHYS 1420: College Physics II
Fall 2009
Quiz 12: Geometric Optics
Answer each of the following questions using your clicker. Questions without multiple choices are true/false, use the T and
F keys to respond. If a numerical answer is required, please express it to the correct number of significant digits, and include the algebraic sign where appropriate. Please do not mark on this quiz paper. Each question is worth 2 points, and
there is no partial credit.
1.
True or false: A single diverging lens cannot magnify text.
2.
True or false: A single converging lens cannot magnify text.
3.
True or false: Converging lenses form right-side-up images only.
4.
True or false: Diverging lenses form right-side-up images only.
A 2–cm tall object is placed 25 cm in front of a converging lens. The image is found 64 cm on the other side of the lens.
5.
The focal length of the lens is
A) 0.011 cm
6.
B)
0.056 cm
C)
15 cm
D) 18 cm
The (absolute value of the) magnification of the image is
A) 0.39
B) 0.72
C)
2.6
D)
7.
The (absolute value of the) image height is
A) 0.78 cm
B) 2 cm
C)
2.7 cm
D) 5.2 cm
8.
The image formed is
A) upright.
B)
inverted.
9.
The image formed is
A) real.
B)
virtual.
3.6
10. An object placed just a tiny bit outside the focal point (do barely > f) of a converging lens
A) forms a real image that is magnified.
C) forms a real image that is minified.
B) forms a virtual, magnified image.
D) forms a virtual, minified image.
11. An object placed exactly at the focal point of a converging lens
A) forms a real image.
B) forms a virtual image.
C)
does not form an image.
12. True or false: Using a multi-lens system, it is possible to create a virtual image of a virtual object. Using a different
lens combination, it is also possible to create a real image of a virtual object.
13. True or false: Chromatic aberration in a lens occurs because blue light has a higher frequency than red, so focuses at a
longer distance.
14. True or false: Converging lens are best to correct far-sightedness.
15. True or false: If you are very nearsighted, you could use the lenses in your glasses to start a signal fire if you are ever
stranded on a deserted island with a planeload of English schoolboys.