Power of an Engine: Work & Effects

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The discussion focuses on calculating the work performed by an engine during a square circuit process and determining the power output based on the time taken for one revolution. The work done by the engine is identified as 1.6 kJ, derived from the area within the square. For power calculation, the correct formula is P = W/t, leading to a power output of 8,000 W when using 1.6 kJ and 0.2 s. A misunderstanding about the multiplication of work and time was clarified, emphasizing that power is the rate of work done. The conversation highlights the importance of correctly applying formulas in physics calculations.
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Homework Statement


An engine goes through a "square" circuit process (is btw "circuit process" this the correct term in English?) according to the diagram below:
attachment.php?attachmentid=73010&stc=1&d=1410425307.png


a) How much work is performed by the engine during one revolution in the circuit process?
b) What effect does the engine deliver if it takes 0.2 s for the circuit process to go through one revolution?

Homework Equations


W = p*V
P = W*t

The Attempt at a Solution


For a) we have simply the area within the square, which is 1.6 kJ.

For b) if we have W = 1.6 kJ and t = 0.2 s, then we should get P = 1.600 J * 0.2 s = 320 W. Why is this not correct?
 

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You should divide, not multiply - power is the rate at which work is done by the engine.
 
Ah yes, of course. :redface: Thanks.
 
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