Conductor charge transfer

Conductor A has an electrical potential of +140V concerning the Earth; conductor B has a potential of -60V. How much electric charge will we transfer from wire B to wire A if we do the work of 4.10-4 Joules?

Final Answer:

Q =  2.0E-6 C

Step-by-step explanation:

$$\begin{gathered} U_1=+140\text{V} \\ {U}_2=-60\text{V} \\ W=4\cdot 10^{-4}=0.0004\text{J} \\ U=U_1-U_2=140-(-60)=200\text{V} \\ W=U\cdot Q \\ Q=W/U=0.0004/200=2.0\cdot 10^{-6}\text{C} \end{gathered}$$

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