Definitions Flashcards
Effort
the force applied to a machine to make it move
elastic collision
an elastic collision is one in which the total kinetic energy after the collision is equal to the total kinetic energy before the collision
elasticity
property of a solid that enables it to regain its shape after it has been deformed or distorted
elastic limit
point beyond which a wire is permanently stretched
electrical conductor
an object that can conduct electricity
electrically insulating materials
an electrical insulator is a material that cannot conduct electricity; a thermal insulator is a material that is a poor conductor of heat
electric field strength, E
at a point in the electric field, is the force per unit charge on a small positively charged object at a point in the field
electric potential, V
at a point in the electric field is the work done per unit charge on a small positively charged object to move it from infinity to that point in the field
electrolysis
process of electrical conduction in a solution or molten compound due to ions moving to the oppositely charged electrode
electrolyte
a solution or molten compound that conducts electricity
electromagnetic induction
the generation of an emf when the magnetic flux linkage through a coil changes or a conductor cuts across magnetic field lines
electromagnetic radiation
an electric and magnetic wavepacket or photon that can travel through free space
electromagnetic wave
an electric and magnetic wavepacket or photon that can travel through free space
electromotive force (emf)
the amount of electrical energy per unit charge produced inside a source of electrical energy
electron
a lepton with rest mass 9.11x10e-31 kg and electric charge -1.60x10e-19 C
electron capture
a proton-rich nucleus captures an inner-shell electron to cause a proton in the nucleus to change into a neutron. An electron neutrino is emitted by the nucleus. An X-Ray photon is subsequently emitted by the atom when the inner shell vacancy is filled.
electron volt
amount of energy equal to 1.6x10e-19 J defined as the work done when an electron is moved through a pd of 1V
endoscope
optical fibre device used to see inside cavities
energy
the capacity to do work
energy levels
the energy of an electron in an electron shell of an atom or the allowed energies of a nucleus
equilibrium
state of an object when at rest or in uniform motion
equipotential
a line or surface in a field along which the electric or gravitational potential is constant
escape velocity
the minimum velocity an object must be given to escape from the planet when projected vertically from the surface
excitation
process in which an atom absorbs energy without becoming ionized as a result of an electron inside an atom moving from an inner shell to an outer shell