As a person pushes a box across a floor, the energy from the person’s moving arm is transferred to the box, and the box and floor become warm. during this process, energy is

The independent variable would be the fertilizer as it is what the dependent variable (the growth of grass) depends on.

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.