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katen-ka-za [31]

2 years ago

5

In each cycle of its operation or refrigerator removes 17 J of heat from the inside of the refrigerator and releases 40 J of hea

t into the room how much work per cycle is required to operate this refrigerator?

1 answer:

Lubov Fominskaja [6]2 years ago

7 0

Answer:

23 J

Explanation:

According to the law of conservation of energy, the total heat given off to the surroundings by a refrigerator is equal to the work done by the refrigerator and the heat removed from the inside of the refrigerator.

So we can write:

$Q_{h} = W+Q_{c}$

where

$Q_{c}$ is the heat removed from the cold reservoir (the inside of the refrigerator)

W is the work done

$Q_{h}$ is the work released into the hot reservoir (the surroundings)

Here we have:

$Q_c=+17 J$ (heat removed from the inside of the refrigerator)

$Q_h=+40 J$ (heat released into the surroundings)

Solving the equation for W, we find the work done:

$W=Q_h-Q_c=40-17=23 J$

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