Calculate Coulomb: Help Solving Homework Problem

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The discussion revolves around calculating the current delivered by batteries for an engine that provides 12 kW of power to move an 800 kg car vertically by 1.5 m. The user attempts to apply the formula I = P/U but is unsure how to determine the voltage (V) needed for the calculation. They mention a misunderstanding of the relationship between joules and coulombs, specifically questioning the meaning of "Js = 12,000." Clarification is sought on how to properly calculate voltage and the associated current. The conversation highlights the importance of understanding electrical units and their interrelationships in solving the problem.
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Homework Statement



The engine delivers 12 kW. Per second it can shift the m = 800 kg car over a vertical distance of 1.5 m. Find the current delivered by the batteries.

Homework Equations



P = U * I
I = P/U = 12 000 W / 168 V = 71.4 A

The Attempt at a Solution



My Problem is: I don't really know how to calculate V...
I know that V = J/C and Js = 12 000, but I don't know how to find out the Coulomb.
Can please someone help?
 
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Physicsrapper said:

Homework Statement



The engine delivers 12 kW. Per second it can shift the m = 800 kg car over a vertical distance of 1.5 m. Find the current delivered by the batteries.
Could you please tell us the problem statement exactly as given to you?

Homework Equations



P = U * I
I = P/U = 12 000 W / 168 V = 71.4 A
Where did you get these numbers from?

The Attempt at a Solution



My Problem is: I don't really know how to calculate V...
I know that V = J/C and Js = 12 000, but I don't know how to find out the Coulomb.
Can please someone help?
A volt is a joule per coulomb, but "Js = 12000" doesn't make any sense.
 

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