Finding Force then converting to work

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The discussion revolves around calculating the average and instantaneous power developed by a car that accelerates from rest to 19.3 m/s over 11.6 seconds, considering a constant air resistance of 400 N. The user initially calculated the work done but was informed that they only found the work and not the power. The key formulas involved include work (W = FΔx) and force (F = ma), with an emphasis on the need to convert work into power by considering time. The user is encouraged to revisit their calculations to ensure they are addressing the power output specifically. Understanding the distinction between work and power is crucial for solving the problem correctly.
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Homework Statement



A 1.50 x 10^3 kg car starts from rest and accelerates uniformly to 19.3 m/s in 11.6 s. Assume that air resistance remains constant at 400 N during this time.

(a) Find the average power developed by the engine.

(b) Find the instantaneous power output of the engine at t = 11.6 s, just before the car stops accelerating.

Homework Equations



W=F(Δx)
F=ma

The Attempt at a Solution



I used kinematic equations to find the Δx at 111.94 and a at 1.663 m/s. (may want to check)

I then used F=ma to find F = 2495.689

then multiplied F by Δx to get 279367.4267 for Work but I am told by my homework website that I am off by a multiple of ten. I can easily guess for the answer but I want to know where I went wrong...

thank you
 
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I do not think there is any mistake in your work. But you were asked for the POWER and you found ONLY the work done up to now.
 

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