When adhesive tape is pulled from a dispenser, the detached tape acquires a positive charge and the remaining tape in the dispenser acquires a negative charge. If the tape pulled from the dispenser has 0.14 micro C of charge per centimeter, what length of the tape must be pulled to transfer 1.8 x 10^13 electrons to the remaing tape?
This problem can be solved with simple units analysis.
Your desired answer is in cm.
You are given a value of charge/cm and a value of electrons.
The solution uses unit analysis to find amount of item necessary to accumulate certain number of electrons, given amount of charge per unit amount of item.