Remote controls use invisible light of frequency just below the visible range. this part of the electromagnetic spectrum is called

Images from reliable sources will suggest and confirm that below the visible light spectrum, there is the infrared.This type of wave has wavelengths of greater than 10^-3 up to 10^-5. Apart from its use in the remote control, infrared can also be used for heat-sensitive thermal camera. 

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.