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3 years ago

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An electrical power plant manages to send 88% of the heat produced in the burning of fossil fuel into the water-to-steam convers

ion. Of the heat carried by the steam, 40% is converted to the mechanical energy of the spinning turbine. Which of the following choices best describes thvall efficiency of the heat-to-work conversion in the plant (as a percentage)?
A. less than 40%
B. exactly 147%
C. 64%
D. greater than 88%
E. 40%

1 answer:

Naya [18.7K]3 years ago

4 0

Answer:

A

Explanation:

Let the x represent the amount of heat generated from the fossil fuel.

88% of x = 0.88 x

0.88 x was used to convert water to steam.

heat carried by steam = 40% × 0.88 x = 0.352 x

efficiency of the heat -to- work conversion = work output / work input = 0.352 x / x = 0.352 × 100 = 35.2 % which is less than 40 %

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Answer:

The height is $h_c = 42.857$

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From the question we are told that

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$mgh_s = \frac{1}{2} mv^2 [\frac{2}{5} +1 ]$

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Substituting this into the conservation equation above

$mgh_c = \frac{1}{2} (mr^2)[\frac{v}{r} ] ^2 + \frac{1}{2} mv^2$

Where $h_c$ is the height where the circular hoop would be released to equal the speed of the sphere at the bottom

$mgh_c = mv^2$

$gh_c = v^2$

$h_c = \frac{v^2}{g}$

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$h_c= \frac{\frac{10gh_s}{7} }{g}$

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Good afternoon.

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2 years ago