Which has the larger light-gathering power?
a. A telescope of 5 cm diameter and focal length of 50 cm.
b. A telescope of 6 cm diameter and focal length of 100 cm.
c. A telescope of 2 cm diameter and focal length of 100 cm.
d. A telescope of 3 cm diameter and focal length of 75 cm.
e. Both b and c since they have the same focal length.
B
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Work Done by a Gas: A compression at a constant pressure of 200 kPa is performed on 8.00 moles of an ideal monatomic gas. The compression reduces the volume of the gas from 0.200 m3 to 0.120 m3. How much work was done by the gas during this process?
A. -16 kJ B. 16 kJ C. -40 kJ D. 40 kJ E. 0 kJ
When water of mass m and specific heat c is heated at constant pressure from absolute temperature T1 to absolute temperature T2, its change in entropy is what?
A. cm ln(T2/T1) B. cm (T2/T1) C. cm (T2?T1)/T1 D. cm (T2?T1)/T2 E. cm (T2?T1)/(T2 + T1)
One good argument in favor of nuclear power over coal power is that
A) the high operating temperature of nuclear plants makes this the most efficient type of generating plant. B) whereas we are running out of coal, there is a very large supply of uranium to supply nuclear power plants. C) nuclear power does not contribute to the ozone problem. D) nuclear plants do not produce any waste heat. E) nuclear power does not contribute to the global warming problem.
A 120-V rms voltage at 2000 Hz is applied to a 6.0-mH inductor, a 2.0-?F capacitor, and a 200-? resistor. What is the rms value of the current in this circuit?
A) 1.5 A B) 0.48 A C) 2.5 A D) 3.5 A E) 0.59 A