A ruby laser beam (? = 694.3 nm) is sent outwards from a 2.7-m diameter telescope to the Moon, 384,000 km away. What is the radius of the big red spot on the Moon?
A. 500 m
B. 250 m
C. 120 m
D. 1.0 km
E. 2.7 km
Answer: C
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Consider a solid cube with a uniform internal charge density ?0. What kind of field does this cube create?
A. Unidirectional B. Axial C. Radial D. None of the above
The oldest carbon isotope evidence of life indicates that life on Earth arose at least
A) 4.5 billion years ago. B) 3.95 billion years ago. C) 2 billion years ago. D) 542 million years ago. E) 65 million years ago.
What is the major problem with the U.S. customary system?
a. It is out of date. b. Understanding the units does not require knowing English. c. It has many different unfamiliar units and conversions are difficult. d. It avoids cumbersome conversions of units. e. It does not allow conversion to metric units.
Which of these wins the prize as the blandest appearing planet as revealed visually by space probes?
a. Jupiter b. Saturn c. Uranus d. Neptune