Physics - Chap 11 Flashcards
Alternating current (AC)
Electric current that flows back and forth at regular intervals called cycles
Ammeter
Device used to measure the current in a circuit
Ampere (A)
Unit of current; a measure of the amount of charge moving past a point in the circuit every second
Battery
Combination of electrochemical cells
Circuit breaker
Safety device in which a wire heats up and bends when there is excess current in the circuit; this triggers a spring mechanism that turns off the flow of electricity
Circuit diagram
Drawing made with symbols that shows the components and connections in a circuit
Current
Continuous flow of electrons in a circuit (number of electrons)
Unit (I): Measure of the amount of electric charge that was added by a point in a circuit each second
Direct current (DC)
Electric current flowing in one direction
Dry cell
Electrochemical cell that uses a paste instead of liquid electrolyte
Circuit
Path for electrons to flow; includes energy source, electrical load, and conducting wires
Load
Device that converts electrical energy to another form of energy
Electrochemical cell
Package of chemicals that converts chemical energy into electrical energy that is sorted in charged particles
Fuel cell
Electrochemical cell that generates electricity directly from a chemical reaction with a fuel, such as hydrogen
Fuse
Safety device in a circuit that has a metal conductor with a low melting point; if the current gets too high, the metal in it melts and the current flow stops
Parallel circuit
Circuit in which the parts are arranged so electrons can flow along more than one path
Potential difference
Difference in electric potential energy between two points that will cause current to flow in a closed circuit; another term for voltage
Potential energy
Energy stored in an object; each electric charge has it
Resistance
Degree to which a substance opposes the flow of electric current through it
Resistor
Any material that can slow current flow in a circuit, such as the filament in a light bulb
Series circuit
Circuit in which the components are arranged one after another in a series
Short circuit
Accidental low-resistance connection between two points in a circuit, often causing excess current flow
Switch
Device that turns a circuit on or off by closing or opening the circuit
Transistor
Tiny device that acts as a switch or amplifier in a circuit
Volt (V)
SI unit for measuring potential differences
Voltage (V)
Difference in electrical potential energy between two points that will cause current to flow in a closed circuit
-speed of electrons through a circuit
Voltmeter
Device used to measure the potential difference between two locations in a closed circuit
Wet cell
Electrochemical cell that has a liquid electrolyte
Ohm
SI Unit for measuring resistance
Ohmmeter
Device for measuring electrical resistance; usually a part of a multifunctional meter called a multimeter
Ohm’s Law
Law stating that as long as temperature stays the same, V=IR, where V is potential difference, I is current, and R is resistance
Ground fault circuit interrupter (GFCI)
Residual current device that detects a charge in current and opens the circuit, stopping current flow
Electrode
Metal strip that reacts with the electrolyte in an electrochemical cell
Electrolyte
Liquid or paste that conducts electricity because it contains chemicals that lose or gain electrons to form ions
