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3 years ago

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Ammonia enters the expansion valve of a refrigeration system at a pressure of 10 bar and a temperature of 22oC and exits at 2.0

bar. The refrigerant undergoes a throttling process. Determine the temperature, in oC, and the quality of the refrigerant at the exit of the expansion valve.

1 answer:

KonstantinChe [14]3 years ago

6 0

Answer:

The the quality of the refrigerant at the exit of the expansion valve is 0.179.

Explanation:

Given that,

Initial pressure = 10 bar

Temperature = 22°C

Final pressure = 2.0 bar

We using the value of h

$h = 293.4\ kJ/kg$

The refrigerant during expansion undergoes a throttling process

Therefore, $h_{1}=h_{2}$

We need to calculate the quality of the refrigerant at the exit of the expansion valve

At 2.0 bar,

The property of ammonia

$h_{f}=47.8 kJ/kg$

$h_{g}=1417.7 kJ/kg$

Using formula

$h_{2}=h_{f}+x(h_{g}-h_{f})$

Put the value into the formula

$293.4 =47.8+x(1417.7-47.8)$

$x=\dfrac{293.4-47.8}{1417.7-47.8}$

$x=0.179$

Hence, The the quality of the refrigerant at the exit of the expansion valve is 0.179.

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As well as the Normal Force $N$ :

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In addition, we know $w=m.g$ , where $m$ is the mass of the block and $g$ the gravity acceleration, which is equal to $9.8m/{s}^{2}$

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On the other hand, we have the following equation that expresses a <u>relation between</u> the distance $d$ with the acceleration $a$ and time $t$ :

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We already know the value of $d$ and calculated $a$ , we have to find $t$ :

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Answer:

The height of Sears Tower is 1448.5 feet.

Explanation:

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Known information

We know that the vertical distance (y) that the ball moves in 9,5s is equal to height of Sears Tower (h).

Too we know that the ball is released from rest, then, $v_{0}$ =0

Height of Sears Tower calculation:

We replace in the equation 1 the data following;

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$h=1448.5 ft$

Answer: The height of Sears Tower is 1448.5 ft

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Complete question:

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Explanation:

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3 years ago

During the class prize-giving ceremony, Anand clapped his hands hard while Kumar clapped his hands softly. Everybody could hear

algol13

Answer:

C - higher volume

Explanation:

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