Answer: work must be done on the system (Option A)
Explanation:
The second law of thermodynamics is the fundamental law of nature; it states that energy can be transferred from cold objects to hot objects only, if work is done on the system. If energy is added to the system then as a result the thermal energy would increase. Second law of thermodynamics is used to determine whether a process is spontaneous or not. Moreover,the second law of thermodynamics is also used in refrigerators.
The answer is A and E.
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Answer:
A time period is denoted by 'T' . It is the time to complete one cycle of vibration. As the frequency of a wave increases, the time period of the wave decreases. The unit for time period is 'seconds
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