Acylinder 8 inches in diameter and 3 ft long is concentric with a pipe of 8.25 inches i. d. between cylinder and pipe there is an oil film. what force is required to move the cylinder along the pipe at a constant velocity of 3 fps

Sorry i don’t know what to do

stands for electromotive force and it is measured in volts. despite its name, it is not actually the force in the sense of being a "pushing" or "pulling" (not measured in newtons).an equation that relates emf,  ℰ,  to a battery's terminal voltage, v, current, i, and internal resistance, r, is    ℰ = v + irin this case, the emf can be interpreted as a voltage—a difference in electric potential.i would not say that it would be considered an energy. if emf can be defined as the energy/work per a unit charge from a battery or other electric source, then it is not strictly energy.