Question

Choose the correct answer:

A- A refrigeration cycle uses 400 kJ of work and delivers 500 kJ of heat to a heat reservoir. The coefficient of performance is:

choices: A: 1.25 B: 0.8 C: 1.8 D: 0.25

B- A heat pump uses 400 kJ of work and delivers 500 kJ of heat to a heat reservoir. The coefficient of performance is:

choices: A: 1.25 B: 1.8 C: 0.8 D: 0.25

C- 2 moles of an ideal gas with a heat capacity ratio of k = 2 undergoes a change in temperature from 100°C to 200°C. The change in internal energy is:

choices: A: 8,314 J B: 4,157 J C: 33,256 J D: 16,628 J

D- 1 mole of an ideal gas undergoes a polytropic process with n = 1.2. The process goes from 1 L and 50°C to 2L and 60°C. Determine the work done in J.

choices: A: -489.6 J B: 415.7 J C: -415.7 J D: 489.6 J

Answer 1