I have a few questions that i need help understanding how to answer:(adsbygoogle = window.adsbygoogle || []).push({});

1. At a power plant, the operating temperatures are 700 C and 310 C. The efficiency of the plant is 65% of its Carnot efficiency. The output of the plant is 500 MW.

a. Determine the efficiency of the plant.

b. What is the power input to the plant?

c. The heat released by the plant is carried away by water. How many kg/sec must pass through the

plant if the maximum allowed temperature increase is 20C?

d. The heat of combustion of coal is 2.8 x 109 J/kg. How many kg of coal must be burned per hour to

supply the plant?

2. An electron initially moves in a horizontal direction midway between two charged parallel plates with a kinetic energy of 2000 eV. The plate separation d = 0.02 m and the length of the plates L=0.040m. The potential difference between the plates is 250 volts.

a. Determine the initial velocity, v, in the position shown.

b. What are the magnitude and direction of the electric field between the

plates?

c. What are the magnitude and direction of the acceleration of the electron

between the plates.

d. What are the magnitude and direction of a magnetic field that, if applied

between the plates, would cause the electron to travel in a straight line?

For the first problem, I have determined that the efficiency of the engine is 26.1%. I can't figure out how to solve question 1b and the rest of the problem. I also don't know how to do problem number 2. Any help that is provided will be greatly appreciated, I need to know how to correctly solve these two problems before my final.

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# What is the power input to the plant?

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