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Free_Kalibri [48]

4 years ago

12

A frictionless piston–cylinder device contains 5 kg of nitrogen at 100 kPa and 250 K. Nitrogen is now compressed slowly accordin

g to the relation PV1.4 = constant until it reaches a final temperature of 450 K. Calculate the work input during this process

1 answer:

Arte-miy333 [17]4 years ago

8 0

Answer:

The work input during this process is -742 kJ

Explanation:

Given;

Initial temperature of nitrogen T₁ = 250 K

final temperature of nitrogen T₂ = 450 K

mass of nitrogen, m = 5 kg

$PV^{1.4} = constant$

The work input during the process is calculated as;

$W = \frac{m*R(T_2-T_1)}{1-n}$

where;

R is gas constant = 0.2968 kJ/kgK

substitute given values in above equation.

$W = \frac{m*R(T_2-T_1)}{1-n} = \frac{5*0.2968(450-250)}{1-1.4} = -742 \ kJ$

Therefore, the work input during this process is -742 kJ

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Answer:

1.44%

Explanation:

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at $x=\dfrac{1}{2}A$ (makes more sense)

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3 years ago

A tall cylinder contains 30 cm of water. Oil is carefully poured into the cylinder, where it floats on top of the water, until t

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Answer:

The gauge pressure is $P_g = 2058 \ P_a$

Explanation:

From the question we are told that

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substituting values

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While $P_o$ is the pressure of oil which is mathematically represented as

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$P_o = 900 * 9.8 * (0.4 - 0.3)$

$P_o = 882 \ Pa$

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