Question 21
Question 21 of 40
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No letter options?
Older MCQs might not have the typical A, B, C, D choices. They have choices 1, 2, 3, and a combination of them is the answer. Below is the key that maps such combinations to the answer.
A 1, 2 and 3 are correct
B 1 and 2 only are correct
C 2 and 3 only are correct
D 1 only is correct
Topics Tested
5. Work, energy and power
5.1. Energy conservation

recall and understand that the efficiency of a system is the ratio of useful energy output from the system to the total energy input

16. Thermodynamics
16.2. The first law of thermodynami...

recall and use the first law of thermodynamics ΔU = q + W expressed in terms of the increase in internal energy, the heating of the system (energy transferred to the system by heating) and the work done on the system