A charge q is transferred from an initially uncharged plastic ball to an identical ball 12 cm away. The force of this attraction is then 17 mn. How many electrons were transferred from one ball to another?

Two trains leave a station at the same time, train a travels at a constant speed of 16 m/s. train b starts at 8.0 m/s but accelerates constantly at 1.0 m/s squared. after 10.0 seconds, which train has the greater speed?