An engine performs 2700 j of work on a scooter. the scooter and rider have a combined mass of 150 kg. if the scooter started at rest, what is the speed of the bike after the work is performed?

Two 2.0-cm-diameter disks face each other, 1.0 mm apart. they are charged to ±10 nc. what is the electric field strength between the disks? a proton is shot from the negative disk toward the positive disk. what launch speed must the proton have to just barely reach the positive disk?