There is a vapor compression type refrigeration cycle using the refrigerant hfc 134 a. in the condenser, it is isostatically cooled, the condensation temperature is 50 ° c., and the condenser outlet is the compressed liquid at 45 ° c. in the evaporator, it is isothermally heated, the evaporation temperature is 10 ° c. and the outlet of the evaporator is heated steam at 15 ° c. when the expansion valve performs isenthalpic expansion, and the adiabatic efficiency of the compressor is 0.70, answer the following questions. (a) calculate the specific enthalpy of the compressor outlet temperature, specific enthalpy, condenser outlet and evaporator outlet. (b) obtain the cooling operation coefficient of this system. (c) obtain the circulation amount of the refrigerant necessary for obtaining the cooling effect of 3.0 kw in this system.

On a average work day more than work place firs are reorted

The filament of an incandescent lamp has a temperature of 2000k. calculate the fraction of radiation emitted in the visible light band if the filament is approximated as blackbody

Tom is having a problem with his washing machine. he notices that the machine vibrates violently at a frequency of 1500 rpm due to an unknown rotating unbalance. the machine is mounted on 4 springs each having a stiffness of 10 kn/m. tom wishes to add an undamped vibration absorber attached by a spring under the machine the machine working frequency ranges between 800 rpm to 2000 rpm and its total mass while loaded is assumed to be 80 kg a) what should be the mass of the absorber added to the machine so that the natural frequency falls outside the working range? b) after a first trial of an absorber using a mass of 35 kg, the amplitude of the oscillation was found to be 10 cm. what is the value of the rotating unbalance? c) using me-3.5 kg. m, find the optimal absorber (by minimizing its mass). what would be the amplitude of the oscillation of the absorber?