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Novosadov [1.4K]

3 years ago

5

An air conditioner running with R-134a on a cycle executed under the saturationdome between the pressure limits of 0.8 MPa and 0

.12 MPa. Calculate themaximum Coefficient of Performance of this heat pump.

1 answer:

ohaa [14]3 years ago

8 0

Answer:

The COP of the system is = 4.6

Explanation:

Given data

Higher pressure = 1.8 M pa

Lower pressure = 0.12 M pa

Now we have to find out high & ow temperatures at these pressure limits.

Higher temperature corresponding to pressure 1.8 M pa

$T_{H} = 62.9$ °c = 335.9 K

Lower temperature corresponding to pressure 0.2 M pa

$T_{L} = - 10.1$ °c = 262.9 K

COP of the system is given by

$COP = \frac{T_{L} }{T_{H} -T_{L} }$

$COP = \frac{335.9}{335.9 -262.9}$

COP = 4.6

Therefore the COP of the system is = 4.6

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$\lambda^{'}-\lambda=\frac{6.626\times 10^{-34} }{9.11\times 10^{-31}\times 3\times 10^{8} } (1-cos157^\circ ) m\\\lambda^{'}-\lambda=2.42\times 10^{-12} (1-cos157^\circ ) m\\\lambda^{'}-\lambda=2.42(1-cos157^\circ ) p.m.$

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From the conservation of momentum,

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Expanding the vector sum, we get

$P^2_{e}=P^2_{\lambda}+P^2_{\lambda^{'}}-2P_\lambda P_{\lambda^{'}}cos\theta$

Now expressing the momentum in terms of De-Broglie wavelength

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$F_{g} = -mgsin(24)$

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Therefore, the magnitude of the work done by the force of gravity on the bike is 14264.6 J.

I hope it helps you!

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