Chapter 5 Work, Energy, Power, and Society (Defs.) Flashcards
(26 cards)
Applying a force on an object that displaces the object in the direction of the force or a component of the force.
Mechanical work (W)
The capacity to do work.
Energy
Energy possessed by moving objects.
Kinetic energy (Ek)
The net amount of mechanical work done on an object equals the object’s change in kinetic energy.
Work-energy principle
A form of energy an object possesses because of its position in relation to forces in its environment.
Potential energy
Energy possessed by an object due to its position relative to the surface of Earth.
Gravitational potential energy
A designated level to which objects may fall; considered to have a gravitational potential energy value of 0J.
Reference level (datum)
The sum of kinetic energy and gravitational potential energy.
Mechanical energy
The total quantity of kinetic and potential energy possessed by the atoms or molecules of a substance.
Thermal energy
Potential energy of protons and neutrons in atomic nuclei.
Nuclear energy
The change of one type of energy into another.
Energy transformation
Energy is neither created nor destroyed; when energy is transformed from one form into another, no energy is lost.
Law of conservation of energy
The amount of useful energy produced in an energy transformation expressed as a percentage of the total amount of energy used.
Efficiency
Energy-rich substance.
Energy resource
A substance that cannot be replenished as it is used in energy-transforming processes.
Non-renewable energy resource
A substance with an unlimited supply or a supply that can be replenished as the substance is used in energy-transforming processes.
Renewable energy resource
Fuel produced by the decayed and compressed remains of plants that lived hundreds of millions of years ago.
Fossil fuel
The decomposition of large, unstable nuclei into smaller, more stable nuclei.
Nuclear fission
A nuclear reaction in which the nuclei of two atoms fuse together to form a larger nucleus.
Nuclear fusion
Radiant energy from the Sun.
Solar energy
Building design that uses the Sun’s radiant energy directly for heating.
Passive solar design
A device that transforms radiant energy into electrical energy.
Photovoltaic cell
Electricity produced by transforming the kinetic energy of a rushing water into electrical energy.
Hydroelectricity
The rate of transforming energy or doing work.
Power (P)
