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• Basal metabolic rate


  The total energy conversion rate of a person at rest
• Chemical energy


  The energy in a substance stored in the bonds between atoms and molecules that can be released in a chemical reaction
• Conservation of mechanical energy


  The rule that the sum of the kinetic energies and potential energies remains constant if only conservative forces act on and within a system
• Conservative force


  A force that does the same work for any given initial and final configuration, regardless of the path followed
• Efficiency


  A measure of the effectiveness of the input of energy to do work; useful energy or work divided by the total input of energy
• Electrical energy


  The energy carried by a flow of charge
• Energy


  The ability to do work
• Fossil fuels


  • Oil
  • Natural gas
  • Coal
• Friction


  The force between surfaces that opposes one sliding on the other; friction changes mechanical energy into thermal energy
• Gravitational potential energy


  The energy an object has due to its position in a gravitational field
• Horsepower


  An older non-SI unit of power
• Joule


  SI unit of work and energy, equal to one newton-meter
• Kilowatt-hour


  Unit used primarily for electrical energy provided by electric utility companies
• Kinetic energy


  The energy an object has by reason of its motion, equal to 1/2 mv^2 for the translational (i.e., non-rotational) motion of an object of mass m moving at speed v
• Law of conservation of energy


  The general law that total energy is constant in any process; energy may change in form or be transferred from one system to another, but the total remains the same
• Mechanical energy


  The sum of kinetic energy and potential energy
• Metabolic rate


  The rate at which the body uses food energy to sustain life and to do different activities
• Net work


  Work done by the net force, or vector sum of all the forces, acting on an object
• Nonconservative force


  A force whose work depends on the path followed between the given initial and final configurations
• Nuclear energy


  Energy released by changes within atomic nuclei, such as the fusion of two light nuclei or the fission of a heavy nucleus
• Potential energy


  Energy due to position, shape, or configuration
• Potential energy of a spring


  The stored energy of a spring as a function of its displacement; when Hooke's law applies, it is given by the expression 1/2 kx^2, where x is the distance the spring is compressed or extended and k is the spring constant
• Power


  The rate at which work is done
• Radiant energy


  The energy carried by electromagnetic waves
• Thermal energy


  The energy within an object due to the random motion of its atoms and molecules that accounts for the object's temperature
• Useful work


  Work done on an external system
• Watt (W)


  SI unit of power
• Work


  The transfer of energy by a force that causes an object to be displaced; the product of the component of the force in the direction of the displacement and the magnitude of the displacement
• Work-energy theorem


  The result, based on Newton's laws, that the net work done on an object is equal to its change in kinetic energy
• Renewable forms of energy


  sources that cannot be used up