Chapter 6 Exam

Question 1

Suppose that two stars are separated in the sky by 0.1 arcsecond. If you look at them with a telescope that has an angular resolution of 0.5 arcsecond, what will you see?

• Two distinct stars.
• One point of light that is the blurred image of both stars.
• Nothing at all

Answer 1

One point of light that is the blurred image of both stars.

Question 2

ace Telescope obtains higher-resolution images than most ground-based telescopes because it is:

• larger.
• closer to the stars.
• above Earth’s atmosphere.

Answer 2

Above Earth’s atmosphere

Question 3

How much greater is the light-collecting area of one of the 10-meter Keck telescopes than that of the 5-meter Hale telescope?

• 2
• 4
• 8
• 16

Answer 3

4

Question 4

Suppose astronomers built a 140-meter telescope. How much greater would its light-collecting area be than that of the 10-meter Keck telescope?
Express your answer using two significant figures.

Answer 4

200

Question 5

Which of the following forms of light can be observed with telescopes at sea level?

• X rays
• ultraviolet light
• visible light
• infrared light
• radio waves

Answer 5

Visible light and Radio Waves

Question 6

If our eyes were sensitive only to X rays, the world would appear __________.

• gray, black, and white like a medical X ray
• brighter than normal because X rays carry more energy -than visible light photons
• dark because X-ray light does not reach Earth’s surface
• green, yellow, and orange, because those are the colors of X rays

Answer 6

dark because X-ray light does not reach Earth’s surface

Question 7

If you had only one telescope and wanted to take both visible-light and ultraviolet pictures of stars, where should you locate your telescope?

• on Earth’s surface
• on a tall mountain
• in an airplane
• in space

Answer 7

In space

Question 8

The James Webb Space Telescope is designed primarily to observe __________.

• visible light
• infrared light
• X-rays
• light of all wavelengths
• gamma rays

Answer 8

infrared light

Question 9

The twinkling of stars is caused by:

• variations in stellar brightness with time.
• light pollution.
• motion of air in our atmosphere.

Answer 9

Motion of air in our atmosphere

Question 10

Which technology can allow a single ground-based telescope to achieve images as sharp as those from the Hubble Space Telescope?

• adaptive optics
• grazing incidence
• interferometry

Answer 10

Adaptive optics