Un pájaro de masa 300 g vuela a una altura de 200 metros a una velocidad de 20 m/s , el pájaro desciende 50 metros y aumenta su velocidad a 25 m/s . Calcular la energía mecánica inicial y final del pájaro y su variación de energía mecánica

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.