7. A complex arrangement of pulleys forms what is called the block in a block and tackle. The rope used to lift the pulleys and the load is the tackle. A block
and tackle is used to lift a truck engine, which weighs nearly 7,406 N. The
force required to lift this weight using the block and tackle is 308.6 N. What is
the mechanical advantage of the block and tackle?

Velocity is the speed of an object in a certain direction so you'd need to know speed and direction

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.