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AysviL [449]
2 years ago
10

A heating system must maintain the interior of a building at TH = 20 °C when the outside temperature is TC = 2 °C. If the rate o

f heat transfer from the building through its walls and roof is 16.4 kW, determine the electrical power required, in kW, to heat the building using (a) electrical-resistance heating, (b) a heat pump whose coefficient of performance is 3.0, (c) a reversible heat pump operating between hot and cold reservoirs at 20 °C and 2 °C, respectively.
Engineering
1 answer:
nasty-shy [4]2 years ago
5 0

Answer:

a)Q_H=16.4kW

b) w=5.467

c)  w=1.2345

Explanation:

From the question we are told that:

Interior temperature TH = 20 °C

outside temperature is TC = 2 °C

Rate H=16.4kW

a)

Generally electric resistance heating is the heat transfer from interior building

Therefore

Q_H=R

Q_H=16.4kW

b)

COP =3

Generally the equation for coefficient of performance is mathematically given by

COP=\frac{Q_H}{w}

Therefore

w=\frac{Q_H}{COP}

w=16.4/3

w=5.467

c)

Generally the equation for coefficient of performance is mathematically given by

COP_r=\frac{TH}{TH-TC}

COP_r=\frac{20+273}{(20+273)-(2+273)}

COP_r=16.2

Therefore

w=1.2345

w=20/16.2

w=1.2345

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PythonA group of statisticians at a local college has asked you to create a set of functionsthat compute the median and mode of
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Answer:

  1. def median(l):
  2.    if(len(l) == 0):
  3.       return 0
  4.    else:
  5.        l.sort()
  6.        if(len(l)%2 == 0):
  7.            index = int(len(l)/2)
  8.            mid = (l[index-1] + l[index]) / 2
  9.        else:
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  11.        return mid  
  12. def mode(l):
  13.    if(len(l)==0):
  14.        return 0
  15.    mode = max(set(l), key=l.count)
  16.    return mode  
  17. def mean(l):
  18.    if(len(l)==0):
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  20.    sum = 0
  21.    for x in l:
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  24.    return mean
  25. lst = [5, 7, 10, 11, 12, 12, 13, 15, 25, 30, 45, 61]
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Explanation:

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20.5

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Answer:

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