Physics Electric Current

what is parallel circuit

a circuit with more than one path for current to flow, current divides up to flow through parts, one goes the other stay

what is a series circuit

a circuit with only one path for current to flow, current moves flow through every part, if one part goes out the whole circuit goes

what happens to lights in a series circuit is one light burns out

all lights turn off

what happens to lights in a parallel circuit if one light burns out

all stay at the same brightness

what is AC circuit

alternating current and is produced by power company and is generated by a generator

how do electrons move in an alternating current circuit

back and forth

what provides the "force" or "push" to move charges in a circuit

battery (potential difference)

what are four ways that you can increase resistance in a wire

change the material to less of a conductor length- longer wires have more resistance size- smaller (narrower) wires have more resistance temp- higher temp have more resistance

in a series circuit what value is constant across all resistors

current (I)

what is DC circuit

direct circuit and flows in one direction and is produced by a battery

kilowatt hour is a measure of what

energy

state Ohm's law

equation that gives the relationship between voltage, current, and resistance V=IR; potential difference is equal to the product of the current and the resistance.

3 examples of common used things that use DC

flashlight, toy car, remote

how do electrons move in a direct current circuit

from positive terminal to negative terminal

alternating current is made by what types of devices

generator

3 examples of common used things that use AC

hair dyer, iron, toaster

in order for current to exist in a circuit, what criteria must be met

it must be a closed path or conducting material (wire) and have a battery that supplies a potential difference

what are three ways you can change the resistance of a wire

length- longer wires have more resistance size- smaller (narrower) wires have more resistance temp- higher temp have more resistance

what is an ammeter and what does it measure

meter that measures current; it is wired in series

resistance

restraint in the flow of charge, ohms

current

the flow of electrons from one place to another (amps)

voltage

the potential difference across a circuit that causes current to flow (electrical pressure) Volts

define electrical power and give its unit

the rate at which energy is used by a circuit (watt)

power

the rate at which energy is used by a circuit, watts (w)

what is the purpose of fuses and circuit breakers in a circuit

these are used to protect the circuit from to much current. they stop the flow of current before reaching equipment

as current flow in a circuit increases what happens to resistance and voltage

voltage increases and resistance decreases; but this doesn't happen spontaneously

in a parallel circuit what value is constant across all resistors

voltage(V)

if there are four resistors wired in series, how may circuit pathways exist

1

if there are 4 resistors wired in parallel, how many circuit pathways exist

4