Chapter 5, Problem 5.104EP

If COP of heat pump is 4, find the efficiency of heat engine working between the same temperature range.

/Heat is transferred from a tank of water in a refrigerator at(OC) degrees to a tank of boiling water at (100 C) degrees. With a reversible machine (heat pump). Calculate the Heat drawn from the refrigerator. if it was The heat transferred to the tank of boiling water is 2254kJ.

In a turbine, steam enters with an enthalpy of 1275 Btu/lb, and leaves with an enthalpy of 1115 Btu/lbm. The transferred heat is 13 Btu/ibm. Find the turbine work in hp where the steam flow rate is 5 lbm/sec?

A computer lab filled with 20 computers and 15 students is cooled by an air conditioningunit on a day where it is 90 oF outside. The room temperature is 72 oF. Assume an averagestudent generate 90 W of heat and each computer generates 150 W of heat. If the COP ofthe air conditioner is 2.5, what power input is required, in kW? If the air conditioneroperated at its maximum coefficient of performance, what power input would be required?

A tank of water has a shaft rotating at 60 rpm with a torque of 40 N-m that is stiring the water. A heater is also present that operates at 120V and draws 4A of current. Heat is then removed from the water such the the total energy content of hte water is constant. How much heat is removed?

Suppose a certain heat engine has an efficiency of 35%. Heat in In order for this heat engine to do 420 J of useful work, how much energy must be taken in as heat from the high- temperature reservoir? 780 J Work 420 J 12 J 150 J 1620 J 1200 J Heat out O O O

When there is heat loss in a system, how can you increase the work output? a. Increase inlet T at the same P b. Increase outlet P

A tank of water has a shaft rotating at 60 rpm with a torque of 40 N-m that is stirring the water. A heater is also present that operates at 120V and draws 4A of current. Heat is then removed from the water such the total energy content of the water is constant. How much heat is removed?

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