a closed path along which elecatrons that are powered by an energy source can flow
what is a voltaic cell?
a source of energy that generates an electric current by chemical reactions involoving two different metals or metal compounds separated by a conducting solution.
what is a battery?
a connection of two or more cells
what is an electrode?
on of two metal terminals in a cell or battery
what is an electrolyte?
a sloution or paste that conducts charge
what is a dry cell?
a cell that contains an electrolyte made of paste
what is a wet cell?
a cell that contains a liquid electrolyte
what is a primary cell?
a cell that can be used only once
what is a secondary cell?
a cell that can be recharged
what is a fuel cell?
a cell that generates electricity through the chemical reactions of fuel that is stored outside the cell
what is a solar cell?
a cell that converts sunlight into electrical energy
what is a terminal?
a posistion on a cell that must be connected to other components to form a circuit
what is a switch?
a control device that can complete or break the circuit to which it is connected
what is an open circuit?
a circuit that contains a gap or break
(gap in wires, switch open)
what is an electric current?
a measure of the number of charged particles that pass by a point in an electric current each second (measured with an ammeter -amperes A)
what is a coulomb (C)?
the quantity of charge that is equal to the charge of 6.25x10^{18 }electrons
what is an ampere (A)?
the unit of electric current, equivalent to one coulomb per second
what is electrical resistance?
the property of a substance that hinnders electric current and converts electrical energy to other forms of energy
what is a resistor?
a device used in an electric current through a component by a specific amount
what is load?
a resistor or any other device that transforms electrical energy into heat, motion, sound or light
eg toaster
what is potential difference (voltage)?
the difference between the electric potential engergy per unit of charge at two points in a circuit
what is a volt?
the unit for potential difference, equivalent to one joule (J) per coulomb(C)
what is a circuit diagram?
a diagram that uses standard symbols to represent the components in an electric circuit and their connections
what is a series circuit?
a circuit in which there is only one path along which electrons can flow
what is a parallel circuit?
a circuit in which there is more than one path alond which electrons can flow
what is Ohm's law?
the ratio of potential difference to current is a constant called resistance
R=
what is an Ohm ?
the unit for resistance, equivalent to one colt per ampere (V/A)
what is a superconductor?
a material through which electric charge can flow with no resistance
what does non-ohmic mean?
Not following Ohm's law
what are the characteristics of loads in series?
the current is the same at any point in a connection;
IT=I1=I2=I3
the potential difference of loads is the sum of potential differences across all the loads;
VT=V1+V2+V3
the resistance is equal to the sum of the resistance of all loads
RT=R1+R2+R3
what are the characteristics of loads in parallel?
the potential difference is the same between terminals of any load -- V_{T}=V_{1}=V_{2}=V_{3}
the current entering loads is equal to the sum of the currents entering all the loads-- I_{T}=I_{1}+I_{2}+I_{3}
the resistance of loads is less than the resistance of the smallest load-- RT<R1; RT<R2; RT<R3