You observe a star cluster with a main-sequence turnoff point at spectral type G (the same spectral type as the Sun). What is the approximate age of this star cluster?
A) 10,000 years
B) 4.6 billion years
C) 10 billion years
D) 100 billion years
E) 10 million years
C) 10 billion years
You might also like to view...
A system performs 800 J of work while taking in 500 J of heat. What is the change in internal energy of the system?
A. not possible. B. 300 J C. -300 J D. 1300 J E. -1300 J
A steel pipe (E 5 190 GPa, ? 5 14 3 1026/°C, d2 5 82 mm, and d1 5 70 mm) of length L 5 4.25 m hangs from a rigid surface and is subjected to a temperature increase ¢T 5 50 °C. The column is fixed at the top and has a small gap at the bottom. To avoid buckling, the mini-mum clearance at the bottom should be approximately:
(A) 2.55 mm
(B) 3.24 mm
(C) 4.17 mm
(D) 5.23 mm
A mixture of ethanol and gasoline is called
a. ethaline. b. gasanine. c. gasohol. d. gethanine.
In the amended Montreal Protocol, many nations agreed to phase out ______________ by the year 2000
Fill in the blank(s) with correct word