An experimenter needs to heat a small sample to 900 K, but the only available oven has a maximum temperature of 600 K. Could the experimenter heat the sample to 900 K by using a large lens to concentrate the radiation from the oven onto the sample as shown above?
A. Yes if the volume of the oven is at least 3/2 the volume of the sample.
B. Yes, if the area of the front of the oven is at least 3/2 the area of the front of the sample.
C. Yes, if the sample is placed at the focal point of the lens.
D. No, because it would violate the conservation of energy.
E. No, because it would violate the second law of thermodynamics.
(GR9677 #91)
Solution:
The second law of thermodynamics:
No process is possible whose sole result is the transfer of heat from a colder to a hotter body.
The oven can only heat the sample to a maximum of 600 K without violating the Second Law.
Answer: E
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