Being the ideal engine, the maximum COP of a Carnot cycle operated in reverse as a refrigerator is
A) (Th/Tc)(1 Tc/Th)-1.
B) 100.
C) (1 Tc/Th)-1.
D) (Tc/Th) (1 Tc/Th)-1.
Question 2When two or more resistors are connected in parallel to a battery
A) the voltage across each resistor is the same.
B) the total current flowing from the battery equals the sum of the currents flowing through each resistor.
C) the equivalent resistance of the combination is less than the resistance of any one of the resistors.
D) all of the other choices are true.
Question 3Which of the following factors in the simplified Drake equation is best known?
A) Nhp, the number of habitable planets in our galaxy
B) fciv, fraction of life-bearing planets where intelligent civilizations have arisen at any time
C) fnow, fraction of civilization-bearing planets that have intelligent civilizations on them now
D) flife, fraction of life-bearing habitable planets
Question 4A turntable was revolving at 33 1/3 rpm. It was shut off and uniformly slowed down and stopped in 5.5 seconds.
(a) What was the angular acceleration?
(b) Through how many revolutions did it turn?
Quick Reply
