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49 tamela12 Please help What is the efficiency of a device that takes in 40,000 J of heat and does 12,000 J of work while giving off 28,000 J of heat? Use and convert to a percentage. A. 57% B. 43% C. 30% D. 70%

User Dyck
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It just depends on what you're trying to accomplish with the device. As a producer of work, it is 12/40 = 30% efficient. As a heater, it is 28/40 = 70% efficient.
User Ooozguuur
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