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
alexandr402 [8]
2 years ago
7

An air conditioner operating between 93°F and 70°F is rated at 4000 Btu/h cooling capacity. Its coefficient of performance is 27

% of that of a Carnot refrigerator operating between the same two temperatures. What horsepower is required of the air conditioner motor? (Halliday, 05/2018, p. 606) Halliday, D., Resnick, R., Walker, J. (05/2018). Fundamentals of Physics, 11th Edition [VitalSource Bookshelf version]. Retrieved from vbk://9781119306856 Always check citation for accuracy before use.
Physics
1 answer:
lana [24]2 years ago
6 0

Answer:P_{in}=0.25\ Hp

Explanation:

Given

Operating temperatures are

T_L=70^{\circ}F\approx 294.261\ K

T_H=93^{\circ}F\approx 307\ K

COP is 27\% of Carnot refrigerator

COP_{carnot}=\dfrac{T_L}{T_H-T_L}

COP_{carnot}=\dfrac{294.261}{307-294.261}

COP_{carnot}=\dfrac{294.261}{12.74}

COP_{carnot}=23.09\approx 23.1

actual COP=0.27 \times COP_{carnot}

COP_{actual}=6.237

Also, COP=\dfrac{\text{Desired effect}}{\text{Power in}}

6.237=\frac{4000}{P_{in}}

P_{in}=\frac{4000}{6.237}=641.33\ Btu/h

P_{in}=0.25\ Hp

You might be interested in
Two uncharged, conducting spheres are separated by a distance d. When charge −Q is moved from sphere A to sphere B, the Coulomb
rosijanka [135]

Answer: a) the force will be repulsive

b) the ratio of the new force to the old force will be 2

c) O

Explanation:

a) since charge -Q is moved from A to B, this implies that sphere A is negatively charged. The two spheres are now negatively charged and will repel themselves.

b) initial force will be -q(-Q)/d2

Adding extra charge -Q will cause change on B to become -2Q

The new force will be - 2Q(-q)/d2

Dividing new force by old force will give 2

C) if B is neutralized, the net charge becomes 0 and there will be no force on it.

3 0
2 years ago
You are lost at night in a large, open field. Your GPS tells you that you are 122.0 m from your truck, in a direction 58.0o east
Drupady [299]

Answer:

The person is 187[m] farther and 70° south to east.

Explanation:

We can solve this problem by drawing a sketch of the location of the person and the truck, then we will draw the displacement vectors and finally the length of the vector and the direction of the vector will be measured in order to give the correct indication of where the person will have to move.

First we establish an origin of a coordinate system.

We can see in the attached schema that the red vector is the displacement vector from the last point to where the truck is located.

The length of the vector is 187 [m], and the direction is 70 degrees south to East.

3 0
3 years ago
Engineers tasked with building a car bumper need high-quality plastic that is readily available. They found the material polycar
jenyasd209 [6]

Answer:

The material must be durable (quality of the material requirement)

Explanation:

The design criteria set for the materials used for technological design are;

1) The materials should be affordable (less costly)

2) The materials should be last for a long duration (high durability)

3) The material should be readily available (easily sourced)

Therefore, given that the engineers initially had the criteria for the required plastic to be of high quality and to be readily available, and that the poly-carbonate they found is long lasting and not too costly, the criteria met that was set initially was the  quality criteria of durability.

7 0
3 years ago
Read 2 more answers
Which equation describes the cosines function for right triangle?
Bogdan [553]

Answer:a

Explanation:

8 0
3 years ago
How does uncertainty relate to measurements and calculations made during an investigation?
DerKrebs [107]
Uncertainty means that your result may be very random, so you can't trust the first or second or so observation, making several samples critical for accuracy. <span />
4 0
3 years ago
Read 2 more answers
Other questions:
  • From the illustration of the potassium atom, fill in the periodic table selection.
    14·1 answer
  • How can we prove air in water​
    14·2 answers
  • A physical property that describes how something feels<br> Is called?
    10·1 answer
  • A student is examining a bacterium under the microscope. The E. coli bacterial cell has a mass of m = 0.200 fg (where a femtogra
    13·1 answer
  • If a shot is put an angle of 41 degrees relative to the horizontal with a velocity of 36 ft/s in the direction of the put, what
    9·1 answer
  • Which source would provide the most reliable information about the safety of nuclear power plants?
    13·1 answer
  • Which of the following is a conversion from light energy to chemical energy?
    15·2 answers
  • Which describes a characteristic of metallic bonds?
    13·1 answer
  • प्रकाशको आवर्तनको परिभाषा लेख्नुहोस् । कन्भेक्स ऐनाको अगाडि तपाई उभियौ भने तपाईको कस्तो आकृति बन्छ, लेख्नर
    9·1 answer
  • 4.2.5 quiz waves and technology
    13·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!