The SI unit of power is Watt (W) which is joules per second (J/s). Sometimes the power of motor vehicles and other machines is given in terms of Horsepower (hp), which is approximately equal to 745.7 watts.
Specific Resistance (”ρ”) is a property of any conductive material, a figure used to determine the end-to-end resistance of a conductor given length and area in this formula: R = ρl/A. Specific resistance for materials are given in units of Ω-cmil/ft or Ω-meters (metric).
Heater resistance is the example for medium resistance.
Kilowatt Hour (kWh) is the commercial unit of electrical energy.; one kilowatt-hour is equivalent to 3.6 megajoule.
A positive temperature coefficient (PTC) refers to materials that experience an increase in electrical resistance when their temperature is raised. Materials which have useful engineering applications usually show a relatively rapid increase with temperature, i.e. a higher coefficient.