The drinking water in a food store in Cebu is made by cooling a tap water in a refrigerated water fountain from 22 to 8 at a flow rate of °C°C 8 kg/hr. If the COP of this refrigerator is 3.1, what is the required power input to this refrigerator?

The heat capacity of an object is:

The work done in a turbine is _____ since it is done by the fluid.

A fuel has the following volumetric analysis: CH_4 = 68%, C_2 H_6 = 32％ Assume complete combustion with 15％ excess air at 101.325 KPA, 21°C wet bulb and 27°C dry bulb. What is the partial pressure of water vapor in kpa?

What is the specific gravity of an oil which has a Baume reading of 28°?

The unit of radioactivity is...

Which of the following valves is the one designed to allow a fluid to pass through in one direction?

The second law of thermodynamics says that whenever energy is exchanged or converted from one form to another, the potential for energy to do work will be _____.

A steam generator on a test generates 885, 000 lb of steam in a 4-hr period. The average steam pressure is 400 psia, the average steam temperature is 700°F, and the average temperature of the feedwater supplied to the boiler is 280°F. If the boiler efficiency for the period is 82.5％ and the coal has a heating value of 13, 850 BTU/lb in actual firing, find the average amount of coal burned in short tons per hour.

Steam entered the cylinder of an engine in such a way that the average pressure is 120 psi. The piston diameter is 10 inches, and the length of stroke is 12 inches. What is the HP of the engine when it is making 300 rpm?

The turbine inlet conditions of a superheat rankine cycle is 17.5 MPa and 530 . It expands in the turbine to 0.007 MPa. The turbine and pump efficiencies are 0.9 and 0.7, respectively. Pressure losses between the pump and the turbine inlet is 1.5 MPa.

A back pressure steam turbine is rated 100 MW. It serves as a prime mover in a cogeneration system. The boiler admits the return water at a temperature of 66 and produces the steam at 6.5 MPa and 455 . °C Steam then enters a back-pressure turbine and expands to the pressure of the process which is 0.52 MPa. Assuming a various location, what is the incremental heat rate for electric?

A steam condenser receives 10 kg per second of steam with an enthalpy of 2570 kJ/kg. Steam condenses into liquid and leaves with an enthalpy of 160 kJ/kg. The cooling water passes through the condenser with temperature increases from 13 to 24 . Calculate the mass flow rate of cooling water passing through the condenser.

A chimney that is made up of steel is better known as _____?

A single-cylinder, double acting, reciprocating steam engine has a bore of 12-inch and an 18-inch stroke. The piston rod diameter is 2-inch. The mean effective pressure both for the head ends and crank ends is 70 psi as shown in the indicator cards. The engine is operating at 92％ efficiency and running at 350 rpm. What is the horsepower output?

In a gas turbine, air enters the compressor at 100 kPa and 27°C and volume flow of 5 m^3/sec. The compressor pressure ratio is 10 and the isentropic efficiency is 85％. At the inlet of the turbine, the pressure is 950 kPa and the temperature is 1,127°C. The turbine isentropic efficiency if 88％ and the exit pressure is 100 kPa. On the basis of an air standard analysis, what is the efficiency of the cycle?

A spring resort in Tuburan, Cebu is developed into a hydro-electric power station. It discharges 205 ft^3/sec and reduces the pressure from 50 psi to 30 psi. Determine the power in KW.

A proposed hydroelectric power plant in mindanao has the following data: Normal headwater elevation: 200 m Normal tailwater elevation: 80 m Friction head loss: 10 m Full turbine discharge: 6.5 m^3/sec Turbine efficiency at rated capacity: 85％ Turbine is directly connected to a 60 cycle AC generator. Determine the effective head of the hydroelectric power plant.

A power plant has a maximum demand of 55 MW with a load factor of 0.70 and capacity factor of 0.5. Estimate the plant capacity.

Which of the following can be used as a coolant in a nuclear plant?

The function of control rods in nuclear plants is to

The sun generates 1 KW per m^2 when used as a source for solar collections. A collector with an area of 1 m^2. The flow rate is 3 liters/min. What is the temperature rise in the water? The specific heat of water is 4,200 j/kg.°C

A counterflow heat exchanger is designed to cool 1.2 kg/sec of oil with specific heat CP = 4.4 kJ/kg.K from 160 to 90 . Water for cooling is available at 23 and flow rate of 2 kg/sec. Calculate the length of a 5 cm inside diameter tubing in meters. The overall coefficient of heat transfer is 84 W/m^2.K.

A single stage air compressor handles 0.454 m^3/sec of atmospheric pressure, 27°C air, and delivers it to a receiver at 652.75 kPa. The volumetric efficiency is 72％, the compression efficiency on an isothermal basis is 85％ and its mechanical efficiency is 90％. If it rotates at 350 rpm, what is the power in kW that must drive it?

A two-stage compressor with an ideal intercooler receives 0.2 kg/sec of Helium at 150 kPa and 27 and discharges it at 7,500 kPa. Calculate the intercooler pressure in kPa.

The total energy released in fission of U is

A cylinder has a bore 15 cm, stroke of 45 cm and volumetric compression is 2, 000 cm^2, find the volumetric efficiency of the engine.

The energy required to be applied to a radioactive nucleus for the emission of a neutron is

The energy required to be applied to a radioactive nucleus for the emission of a neutron is

Which of the following type of pump is used in liquid metal cooled reactor for circulation of liquid metal

Artificial radioactive isotopes find application in

Air enters a compressor at atmospheric conditions of 25 and 80 °C kPa and exits at 900 kPa and 250°C. Calculate the rate of heat transfer if the power input is 500 kW. The air exits at 30 m/sec through the exit diameter of 100 mm.

A reciprocating compressor is to deliver 30 kg/min of air at 1,800 kPa. It receives atmospheric air at 23°C. Calculate the required power if the compressor is assumed to be 90％ efficient. Neglect the effects of cooling.

A steam plant operates with initial conditions of 1.7 MPa and 370°C and exhaust to a heating system at 0.17 MPa. The condensate from the heating system is returned to the boiler at 65.5°C and the heating system utilizes from its intended purpose 90％ of the energy transferred from the steam it receives. The thermal efficiency is 70％, if the boiler efficiency is 80％, what is the cogeneration efficiency of the system? Just neglect the effect of the pump work.

In a pump installation, the rate of water flow is 60.6 kg/sec. The intake static gage is located 1.22 m below the pump centerline and reads 68.95 kPa gage, the discharge static gage is 0.61 m below the pump centerline and reads 344.75 kPa gage. The gages are located close to the pump as much as possible. The area of the intake pipe is 0.093 m^2 and that of the discharge is 0.069 m^2. Pump efficiency is 70％ and use density of 1000 kg/m^3. Calculate the hydraulic power in kW.

It is desired to deliver 5 cubic meter per second at a head of 640 m in a single stage pump having specific speed not to exceed 40. If the speed is not to exceed 1352 rpm, how many stages are required?

A pump receives 8 kg/sec of water at 220 kPa and 110 °C discharges it at 1,100 kPa. Compute for the power required in kW.

A 30 cm x 40 cm reciprocating pump running at 250 rpm discharges 0.210 m^3/sec of water. Find the percent slippage of the pump.

What is the static air power in watts of a fan designed to deliver 1,000 m^3/hr of air with a static pressure of 10 cm of water column on full delivery?

A company manufacturing fans and blowers has the following product specifications: 15 cm of water static pressure at 180 m^3/min of air at 21°C, 1,200 rpm, 760 mmHg barometric pressure and 75％ static efficiency. What is the new shaft horsepower at 2,000 rpm, 85°C, and 600 mmHg barometric pressure?

A reverse carnot refrigeration cycle requires 3 Hp and extracts energy from a lake to heat a small office. If the small office is kept at 70 and requires 2,000 BTU per minute, what is the temperature of the lake?

The evaporative condenser of an ammonia refrigeration plant has a water flow rate of 126 kg/sec and enters a natural draft cooling tower at 40. The water is cooled to 29 by air entering at 38 db and 24 wb. The air leaves the tower as saturated at 40 db. What is the needed make-up water in kg/hr?

Referring to the values displayed in the steam table, as the saturation temperature increases, what happens to the volume of saturated vapor?

Express 1 TR to kCal/min

One metric ton of fish is to be refrigerated from 30 to -5 in 10 hrs. The freezing temperature is -1, the specific heats below and above freezing temperature are 0.4 kJ/kg. and 0.8 kJ/kg., respectively, and the latent heat is 435 kJ/kg. Allow additional heat load to compensate for heat losses. Determine the refrigerating load in tons of refrigeration.

The temperature registered by a thermometer whose bulb is covered by a wetted wick and exposed to a current of rapidly moving air.

How many tons of ice can be made by 20-ton ice plant in 24 hours from raw water at 80 to ice at 5?

In a refrigeration system, R-314a is compressed from 200 kPa to 1000 kPa in an 83％ efficient compressor. The condensing temperature is 40°C. Calculate the coefficient of performance of this refrigeration system.

In a refrigeration system, R-314a is compressed from 200 kPa to 1000 kPa in an 83％ efficient compressor. The condensing temperature is 40°C. Calculate the mass flux for 60 tons of refrigeration.

An air-vapor mixture is at 24°C, 101.3 kPa, and 50％ RH. What is the specific volume of this air-vapor mixture in m^3/kg? At 24°C, Psat = 2.982 kPa.

A mechanical draft cooling tower cools the water from 60 to 25 °C at the rate of 41,500 kg/sec. Atmospheric air enters the tower at 20 °C and leaves at 35. The fan is driven by a 7460-kW motor. What is the mass flow rate of the air into the cooling tower?

An evaporator has a cooling capacity of 12,000 BTU/hr with a sensible heat ratio of 0.85. What is the latent cooling capacity?

Which of the thermodynamic properties best describes the molecular activity of a substance?

A 65％ efficient cooling tower is designed to cool water at 55°C. The ambient air is 32°C db and 27°C wb. The heat rejected in the condenser is 640 kW. What is the capacity of the pump used in this cooling tower? Use specific volume of water as 1.0067 liters/kg.

The Mach number is unity at the location of the smallest flow area, called the _____

In an air standard Otto cycle, the clearance volume is 12％ of the displacement volume. What is the thermal efficiency?

This refrigeration system component combines the functions of a cooling tower and a condenser. It consists of a casing enclosing a fan or blower section, water eliminators, refrigerant condensing coil, water pan, float valve, and spray pump outside the casing. What do you call this component?

What is the standardized term used by the industry to describe any device that meters or regulates the flow of liquid refrigerant to an evaporator?

What is true about steam as it condenses?

What is true about steam as it condenses?

The temperature at which the condensation of water vapor in a space begins for a given state of humidity and pressure as the temperature of the vapor is reduced. This is the temperature corresponding to saturation for a given absolute humidity at constant pressure.

If the sensible heat ratio is 0.75, what does it mean?

Calculate the use factor of a 135 MW plant with a load factor of 0.8 and peak load of 120 MW if its operation is limited to 8500 hrs in a year

Maximum demand of 30 MW and 10 MW are connected to a power plant with a peak load of 70 MW. What is the diversity factor of the plant?

Which of the following is not a solid fuel?

Pump whose purpose is to increase the effective water pressure by sucking water from public service main or private-use water system

A solid of diameter D = 0.5 m and surface emissivity of 0.8 contains electrons that dissipate 100 W of heat. If it does not receive radiation from the surroundings, what is the surface temp?

Shear stress in a turbulent flow is given by the formula τ = η (du / dy) Where η (eta)is,

The highest point of syphon is called as

Which of the following number is applicable in open hydraulic structure such as spillways, where gravitational force is predominant?

One liter of a certain fluid weighs 8 N. What is its specific volume?

According to Archimede’s principle, if a body is immersed partially or fully in a fluid then the buoyancy force is _____ the weight of fluid displayed by the body.

A device that violates either the first law of thermodynamics or the second law of thermodynamics is known as _____.

An air bubble rises from the bottom of a well where the temperature is 25°C, to the surface where the temperature is 27°C. Find the percent increase in the volume of the bubble if the depth of the well is 5 m. atmospheric pressure is 88.1 kPa.

Any characteristic of a thermodynamic system is called a _____.

The compressor inlet temperature in a gas turbine plant is 99°C. Calculate the compressor air exit temperature if it requires 400 kJ/kg of work.

A 4 stroke, direct injection diesel engine of 4 inches bore and 4.5 inches stroke develops 45 Hp at full load and 8 Hp when running at idling load. Engine speed is 2,200 rpm. What is the mechanical efficiency?

In a steam power plant, shaft work is fed to the _____ for getting an electrical output.

The steam from a steam generator of a nuclear power plant is best described as _____.

Determine the indicated power of a four-cylinder, 4-stroke, diesel engine with 20-cm bore and 30-cm stroke running at 1000 rpm and has reading of 450 kPa mean effective pressure in the indicator diagram.

Rate of energy released by the combustion of the fuel is given by

The efficiency of the boiler is given by

A 80 MW power plant has an average load of 34,500 kW and a load factor of 0.75. Find the reserve power over a peak load power.

In a cooling tower, the water is cooled mainly by;

Control rods for nuclear reactors are made of

A diesel power plant uses fuel with a heating value of 45,038.8 kJ/kg. What is the density of fuel at 30°C?

A closed system may refer to _____.

What refers to the measure of the disorder present in a given substance or system?

The brake thermal efficiency of a 1 MW diesel electric plant is 36%. Find the heat generated by fuel in kW if the generator efficiency is 89%.

What is the daily average load in a certain power plant if the daily energy produced is 500,000 kW-hrs?

What is considered as the actual pressure at a given position and is measured relative to absolute vacuum?

Which statement of the second law of thermodynamics states that no heat engine can have a thermal efficiency of 100 percent?

What states that for a confined fluid, the pressure at a point has the same magnitude in all directions?

What remains constant during a steady-flow process?

What is a process in which the system remains infinitesimally closed to an equilibrium state at all times?

The heat flow rate is directly proportional to the change of temperature with respect to the length of the heat flow path. This statement is true as per _____.

In natural convection, the fluid molecules are displayed due to _____.

A non-dimensional number generally associated with natural convection heat transfer is

Reynolds number is the ratio of

Thermal conductivity of solid metals with rise in temperature normally

The thermodynamic properties that are independent on the size of the system is called _____.