1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
ss7ja [257]
2 years ago
11

A refrigerator operating on the Carnot cycle is used to make ice. Water freezing at 32oF is the cold reservoir. Heat is rejected

to a river at 72oF. Determine the work required to freeze 2000 lbm of ice if the energy required to freeze ice is 144 Btu/lbm. What is the power input required in kW and hp is this operation is carried out in 1 hour? [20] Hint: use the max. possible COP equations.
Engineering
1 answer:
Mnenie [13.5K]2 years ago
7 0

Answer:

Explanation:

From the given information:

Water freezing temp. T_L = 32 ^0 \ F

Heat rejected temp T_H = 72 ^0 \ F

Recall that:

The coefficient of performance is:

COP_{ref} = \dfrac{T_L}{T_H - T_L} \\ \\  = \dfrac{32+460}{(72 +460) -(32+460)} \\ \\ =\dfrac{492}{532 -492} \\ \\ = \dfrac{492}{40} \\ \\ COP_{ref} = 12.3

Again:

The efficiency given by COP can be represented by:

COP = \dfrac{Q_L}{W} \\ \\ W = \dfrac{Q_L}{COP} \\ \\ W = \dfrac{2000 \ lbm \times 144 \ Btu/lbm}{12.3} \\ \\ W = 23414.63 \ Btu

Finally; the power input in an hour can be determined by using the formula:

Power= \dfrac{W}{t} \\ \\  Power = \dfrac{23414.63 \ Btu}{ 1 \ hr} \\ \\  Power = \dfrac{23414.634 \times 1055.056 \ J}{1 \times 3600} \\ \\  Power  = 6.86 \ kW

In hp; since 1 kW = 1.34102 hp

6.86kW will be = (6.86 × 1.34102) hp

= 9.199 hp

You might be interested in
A 50-kN hydraulic press performs pressing and clamping actions. The clamping cylinder force is 4 kN. The pressing cylinder strok
galben [10]

Answer:

The attached figure shows the hydraulic circuit using one sequence valve to control two simultaneous operations performed in proper sequence in one direction only. In the other direction, both the operations are simultaneous.

When we keep the 4/2 DCV in crossed arrow position, oil under pressure is supplied to the inlet port of the sequence valve. It directly flows to Head end port-1. Hence Cylinder 'C1' extends first.

By the end of the extension of cylinder 'C1', pressure in the line increases and hence poppet of sequence valve is lifted off from its seat and allows oil to flow to port-2 and hence, Cylinder 'C2 extends completing the pressing operation.

In the straight-arrow position of 4/2 DCV the oil under pressure reaches the rod end of both the cylinders C1 and C2 simultaneously through port-3. This causes both the cylinders to retract simultaneously.

Also, a Flow control valve is provided tho control the velocity of clamping

Explanation:

find attached the figure

4 0
3 years ago
Which measuring tool will be used to determine the diameter of a crankshaft journal?
guapka [62]

Answer:

The dial bore gauge measures the inside of round holes, such as the bearing journals. This one tool can measure 2″ up to 6″ diameter holes. Both tools are needed in order to check the interior and exterior dimensions of the crankshaft, rods and engine block journals, as well as the thickness of the bearings themselves.

Hope it's helpful to you

pls mark me as brain list

4 0
3 years ago
Find three examples of good websites and three examples of bad websites. List them below, and in a
Fudgin [204]

Answer: its c

Explanation:

4 0
2 years ago
The National Electrical Code specifies that receptacles in certain areas of a house must have ground fault circuit interrupter p
Kaylis [27]

Answer:

b

Explanation:

the NEC has expanded the requirements for ground-fault circuit interrupters (GFCI) to protect anyone who plugs into an electrical system. Initially, it was only required for temporary wiring at construction sites and in dwelling unit bathrooms, but in recent years the Code requirements for GFCI protection have expanded to include many other areas, including commercial occupancies, fountains and swimming pools, and temporary installations, to name a few. (For a complete list of 2002 NEC references, see the sidebar below)

6 0
2 years ago
18) Technician A says that adjustable wrenches should be used when
kykrilka [37]
Tryna boost my score for college stuff could you give me the brainiest and a thanks? Hope you find your answer your looking for!
4 0
2 years ago
Other questions:
  • Water at 15°C is to be discharged from a reservoir at a rate of 18 L/s using two horizontal cast iron pipes connected in series
    6·1 answer
  • The rigid beam is supported by a pin at C and an A992 steel guy wire AB of length 6 ft. If the wire has a diameter of 0.2 in., d
    14·1 answer
  • A hydraulic cylinder has a 125-mm diameter piston with hydraulic fluid inside the cylinder and an ambient pressure of 1 bar. Ass
    8·1 answer
  • A cooling system load is 96,000 BTUh sensible. How much chilled air is required to satisfy the load if the system is designed fo
    12·1 answer
  • A heat engine receives heat from a heat source at 1453 C and has a thermal efficiency of 43 percent. The heat engine does maximu
    11·1 answer
  • In an experiment, the local heat transfer over a flat plate were correlated in the form of local Nusselt number as expressed by
    5·1 answer
  • A rotor in a compressor stage has a mean blade radius of 0.285 m and an angular rotor velocity of 8500 RPMs. The static temperat
    9·1 answer
  • Your local hospital is considering the following solution options to address the issues of congestion and equipment failures at
    6·1 answer
  • "Transformer is used to change the voltage".
    5·1 answer
  • Technician a says that personal protective equipment (ppe) does not include clothing. technician b says that the ppe used should
    14·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!