Doing physics quiz corrections: One of the questions asks which quantities can be graphed on the x and y-axis that could be used to determine the coefficient of kinetic friction and the answer was to graph height (h) and distance (x) on their respective axis. then the slope (h/x) would be the μk. Why does this happen?

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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.