An insulated piston-cylinder device contains 0.15 of saturated refrigerant-134a vapor at 0.8 mpa pressure. the refrigerant is now allowed to expand in a reversible manner until the pressure drops to 0.2 mpa. determine the change in the exergy of the refrigerant during this process and the reversible work. assume the surroundings to be at and 100 kpa.

Acertain flow of air (at stp) has a velocity distribution given by v i (in ft/s). if this flow is going through a 4 ft square area in the yz-plane (centered at the origin), what is the mass flow rate (in lbm/s)?

An external consultant recommends that a plant installs a bank of capacitors for power factor correction. this will reduce the peak electrical demand charges by an average of 93 kw every month. the plant current pays $13 per kw in peak demand charges. the capacitor bank will include 223 kw of fixed capacitors, and 183 of variable capacitors. the fixed capacitors cost $59 per kw, and the variable capacitors will cost $65 per kw. the consultant charges 21% of the equipment costs to install the capacitors. because this project will reduce the demand for the electric utility, they are prepared to provide a one-time rebate of $42 per kw of reduced demand. what is the simple payback period for this project (in years)?

Aplate of dimensions 3 m x 3 m is placed 0.37 mm apart from a fixed plate. the plate requires a force of 2n to move at speed of 45 cm/s. evaluate the viscosity of the fluid in between the plates