Respuesta :
An electrical power plant manages to send 88% of the heat produced in the burning of fossil
fuel into the water-to-steam conversion. 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
the overall efficiency of the heat-to-work conversion in the plant (as a percentage)?
a. greater than 88%
b. 64%
c. less than 40%
d. 40%
Answer:
Option C is correct
Explanation:
This is the final heat transfer into mechanical energy / total energy production by fossil fuel
Let x = total heat produced by fossil fuel
-88% of x was used to convert water to steam so therefore
.88 *x = 0.88x
- 40% of heat in steam was converted to final mechanical work so therefore
0.4 * 0.88x = 0.352x
So therefore:
Overall efficiency = (0.352x/ x ) * 100 = 35.2%
So therefore option C is correct
