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loris [4]
2 years ago
13

A food department is kept at â12°c by a refrigerator in an environment at 30°c. the total heat gain to the food department is

estimated to be 3300 kj/h and the heat rejection in the condenser is 4800 kj/h. determine the power input to the compressor, in kw and the cop of the refrigerator
Physics
1 answer:
slava [35]2 years ago
3 0

As per energy conservation in the reversible engine we can say

Q_2 + W = Q_1

here we know that

Q_2 = 3300 kJ/h

Q_1 = 4800 kJ/h

now from above equation

3300 + W = 4800

W = 1500 kJ/h

now we can convert it into kW

W = 1500\times \frac{kJ}{3600s}

W = 0.42 kW

so above is the power input to the refrigerator

now to find COP we know that

COP = \frac{Q_2}{W}

COP = \frac{3300}{1500} = 2.2

so COP of refrigerator is 2.2

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man stands on a platform that is rotating (without friction) with an angular speed of 1.2 rev/s; his arms are outstretched and h
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Answer:

w₂ = 22.6 rad/s

Explanation:

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final moment. After releasing the bricks

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       w₂ = I₁ / I₂ w₁

let's reduce the data to the SI system

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 let's calculate

       w₂ = 6.0/2.0   7.54

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Answer:

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