As shown in the figure below, Refrigerant 134a is contained in a piston-cylinder assembly, initially as saturated vapor. The refrigerant is slowly heated until its temperature is 150°C. During the process, the piston moves smoothly in the cylinder. Weight 471.1 N D= 0.02 m Patm=I bar 3D Piston Initial: Saturated vapor Final: T2 Refrigerant 134a in l1/le

By actual measurement, the enthalpy of steam at 8 bar is found to be              3000 KJ/Kg. What is the quality of steam? If 500KJ/Kg of heat is added to this steam, what is the (i) Superheated temperature (ii) Degree of superheat (iii) Enthalpy of superheat?

4. One mole of helium gas is injected into each side of a slidable, airtight lead piston that separates two chambers of a sealed cylinder. The outside of the cylinder is insulated everywhere except where noted below. The cylinder and piston have lengths and cross- sectional area labeled in the diagram. The helium in the left chamber is heated from outside at a rate of 450 W, and the helium in the other chamber expels heat into a cool region. The full system eventually comes to steady-state. When it reaches steady state, the force needed to hold on the end cap is measured to be 18,000 N, and the piston has slid to an equilibrium point that is a distance à from the left end. force holding cap = 18,000N pressure. cross-sectional area of cylinder = 0.02m² x = ? Imol He do dt = +450W 45cm 15cm lead piston a. Find the temperature difference of the two chambers. b. Find the distance x. dQ dt Assume helium behaves as an ideal gas, and that heat transfer through the container walls is…

4. At a pressure of 900 kPa, the specific enthalpy is 2000 kJ/kg. What is the phase of the water? a. Solid b. Solid-liquid mixture c. Subcooled liquid d. Saturated liquid e. Saturated mixture f. Saturated vapor g. Superheated vapor For the water in problem 4, determine the following: a. If saturated mixture calculate the quality, x = b. Determine the specific internal energy.