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A closed-loop or cyclic process is a process that starts and ends at the same point. The system returns to its initial state implying that initial and final states are the same. The PV diagram below shows the cyclic process for a gas sample. Determine the net work done by the gas during the process and verify that its magnitude is equal to the area of the loop.
1.00 × 10-2 mol of argon gas is utilized as the operational fluid in a thermal engine. The cyclic process of the thermal engine is represented in the pV diagram below. Calculate the net work done by the gas, the heat energy added to the gas, and the variation in the internal energy during the cycle. The temperatures at points A, B and C respectively are: TA = 7.22×102 K, TB = 1.20×103 K, TC = 9.80×102 K and the volume at point C is VC = 543 ×10-6 m3.
Nitrogen gas serves as the working fluid in a thermal engine. The pV diagram of the thermal engine's cyclic transformation is shown below. Calculate the thermodynamic state of nitrogen at point B.
A thermal engine utilizes 1.5 mol of neon gas as its operating fluid. The pV diagram shown below illustrates the cyclic process of the engine. Calculate the temperatures at points A, B, and C.
A thermal engine uses helium as the working fluid. At point A, helium is initially at a temperature of 300 K while the temperature at point C is 750 K. The pV diagram of the thermal engine's cyclic transformation is shown below. Calculate the heat Q during the transformation AB. Hint: Calculate W and ΔEintfirst.
A model of the lungs is made of a balloon, a glass container, and a movable diaphragm. A straw is used to connect the balloon to the atmosphere. The balloons are inflated when the diaphragm is pulled downward and deflated when the diaphragm is released. An ideal PV diagram for the process is shown below. The actual PV diagram has curves, not straight lines. The pressure used is gauge pressure, not absolute pressure. This process differs from other processes in that pressure variations are caused by changes in the quantity of gas rather than changes in temperature. If the model is operated at a temperature of 25°C, determine the greatest number of moles of gas attained in the balloon.
