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What is Electrical Work Transfer ?

 When a current flows through a resistor, taken as a system, there is a work transfer into the system. This is because the current can drive a motor, the motor can drive a pulley and the pulley can raise a weight. 




The current flow, I, in amperes, is given by 

I= dC / dt

Where C is the charge in the coulombs and t is time in seconds. Thus the dC is the charge crossing a boundary during time dt. If E is the voltage potential, the work is 

dW = E.dC = EI dt 

W = lim dt --->0  ( dW / dt ) = EI 

This is the rate at which work is transferred. 

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