(Solved): A plastic rod is rubbed with wool, producing a distribution of positive and negative surplus charge ...

A plastic rod is rubbed with wool, producing a distribution of positive and negative surplus charge that is concentrated in two locations on the rod and two on the wool. This distribution can be approximated as two pairs of small balls of charge as shown in (Figure 1). The distance \( \mathrm{d} \) is \( 30.0 \mathrm{~mm} \), and the magnitude of the charge on each ball is \( 7.00 \mu \mathrm{C} \). The initial state of the system is the neutral rod and wool before the rubbing. If \( 34.0 \) J of work went into thermal energy as the rod and wool heated up, how much work was done on the system? Express your answer with the appropriate units.