| Glossary | ||||||||||||||
| elastic potential energy
— potential energy stored in an object that is transformed into kinetic energy when the object itself is transformed in shape, configuration, or length. elasticity — property of a material to bend or deform without breaking. Rubber is very elastic while glass is not. electric charge — fundamental property of matter that comes in two varieties we call positive and negative. electric circuit — electrical device that has a complete or continuous path that electricity can flow through. electric current — flow of electric charges, usually in wires or other conductors. Measured in amperes (A). electric field — force field created by electric charge. Electric field is a vector with the direction that a positive test charge would move, and whose magnitude is the force per unit charge. Measured in force per unit charge with units of newtons per coulomb, abbreviated N/C. electric field lines — vector arrows that depict visually the direction and magnitude of an electric field. electric force — fundamental force that charged objects exert on each other. electric motor — machine that transforms or converts electrical energy into mechanical energy. electric potential — electrical potential energy per unit charge for an electric field. electric potential energy — change in potential energy per unit charge in an electric field. electrical conductor — material, such as a metal, that offers low resistance to the flow of electric current. electrical generator — machine that converts rotational motion to electricity electrical insulator — material that is a poor conductor of electric current. electrical symbol — symbol used to represent a component of a circuit in a circuit diagram. | electrically neutral
— object that has a net charge of zero. electricity — flow of electric current through a conductor, such as a wire. Electricity is sometimes also used to describe electrostatic charges. electromagnetic induction — inducing (or creating) a voltage in a conductor by changing the magnetic field near the conductor. electromagnetic spectrum — range of frequencies of electromagnetic radiation extending from low frequencies (radio waves and microwaves) to higher frequencies (infrared radiation, visible light, ultraviolet light, x-rays, and gamma rays). electromagnetic wave — transverse wave resulting from oscillating and perpendicular electric and magnetic fields and traveling at the speed of light. Also called electromagnetic radiation. Examples of electromagnetic waves, in order of increasing wavelength, are gamma rays, x-rays, ultraviolet radiation, visible light, infrared radiation, microwaves, and radio waves. electromagnetism — interaction of electric currents (or fields) and magnetic fields. electromagnets — magnets that are created by the flow of electricity. electron — negatively charged subatomic particle with a mass of 9.109×10-31 kg and a charge of −1.602×10-19 C. electron volt (eV) — unit of energy corresponding to the amount of energy gained by an electron that moves across a potential difference of one volt (V). One eV is equal to 1.602×10−19 J, which corresponds to one volt multiplied by the charge of the electron. electroscope — scientific instrument used to detect charged objects. electrostatic induction — process of electrically charging an object by holding it close to another charged object. electrostatics — study of electric charges at rest. elementary charge — indivisible electric charge carried by a single proton (positive) or electron (negative). Usually denoted e and equal to 1.602×10−19 coulomb (C). | |||||||||||||
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