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skelet666 [1.2K]
3 years ago
8

R-134a vapor enters into a turbine at 250 psia and 175°F. The temperature of R-134a is reduced to 20°F in this turbine while its

specific entropy remains constant. Determine the change in the enthalpy of R-134a as it passes through the turbine.
Engineering
1 answer:
attashe74 [19]3 years ago
5 0

Answer:

Δ enthalpy = -23 Btu/Ibm

Explanation:

Given data:

Pressure ( P1 ) = 250 psi

Initial Temperature ( T1 ) = 175°F

Final temperature ( T2 ) = 20°F

<u>Calculate the change in the enthalpy of R-134a </u>

From R-134 table

h1 = 129.85 Btu/Ibm

s1 = 0.23281 Btu/Ibm.R

note : entropy is constant  

hence ; s1 = s2

by interpolation  ; h2 = 106.95

Δ enthalpy = h2 - h1

                  =  ( 106.95 - 129.85 ) = -23 Btu/Ibm

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Answer:

-50.005 KJ

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7 0
3 years ago
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Discuss the organizational system that you believe would be the most effective for the safety officer in a medium-sized (100-200
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Answer:

A safety manager is a person who designs and maintains the safety elements at workplace. A balance should be required for production and the job in providing work environment. As a safety officer in a medium sized manufacturing facility the following organizational system can be designed and maintained:

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3 0
3 years ago
we wish to send at a rate of 10Mbits/s over a passband channel. Assuming that an excess bandwidth of 50% is used, how much bandw
gayaneshka [121]

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Explanation:

See attached picture.

6 0
3 years ago
For each function , sketch the Bode asymptotic magnitude and asymptotic phase plots.
horrorfan [7]

Answer:

attached below

Explanation:

a) G(s) = 1 / s( s+2)(s + 4 )

Bode asymptotic magnitude and asymptotic phase plots

attached below

b) G(s) = (s+5)/(s+2)(s+4)

phase angles = tan^-1 w/s , -tan^-1 w/s , tan^-1 w/4

attached below

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solution attached below

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3 years ago
An amplifier which needs a high input resistance and a high output resistance is : Select one: a. A voltage amplifier b. None of
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Answer:

None of these

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Therefore, the correct answer is "None of these "

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