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Current:define,unit,equation

the flow of electrons

unit: amp

I=V/R

unit: amp

I=V/R

Coulomb

#of electrons per second: 6.25 x 10^8

Potential Difference:aka, definition, units, equation

aka:Voltage

Definition:electrical pressure

unit: volt

equation: V=IR

Definition:electrical pressure

unit: volt

equation: V=IR

Resistance: definition, unit, equation

inhibits or impedes electron flow

unit: ohm

R=V/I

unit: ohm

R=V/I

Open Circuit

when the switch is off, no place for electrons to go, electron transportation is incomplete

Closed Circuit

switch is on, switch connects the ends of open circuit, electrons allowed to flow

direct current

electrons flow in ONE direction, ex: battery

alternating current

electrons have reverse direction, EX: anything plugged in

things that affect resistance of wire

Length(L direct prop to R)

Thickness(R indirect prop to diameter^2)

Composition-exof good:gold, ex bad:nichrome

Temp(T direct to R)

Thickness(R indirect prop to diameter^2)

Composition-exof good:gold, ex bad:nichrome

Temp(T direct to R)

Rheostat

dimmer switch

Ohms law

V direct Prop to I, I indirect to R

Series circuit: problems, relation with volts and currents, use, equation

Problems: if 1 goes out-all go out, all appliances must be on 24/7, appliances wont work without proper voltage

relations: volts are shared, current is the same in each resistor

use: blinking lights

equation:RT=R1+R2+etc

relations: volts are shared, current is the same in each resistor

use: blinking lights

equation:RT=R1+R2+etc

Parallel Circuits: reasons to us, relations with volts and currents, equation

Reasons: if 1 goes out-rest are on, dont have to be on 24/7, each appliance gets same voltage

Relations: currents are shared, volts are the same

Equation: 1/RT=1/R1+1/R2+...

Relations: currents are shared, volts are the same

Equation: 1/RT=1/R1+1/R2+...

Power equation

P=IV

Energy equation

E=PT

Final Cost equation

FC=E(cost/hour)

Heat equations

Q=R(I^2)(Time)

Q=Power(time)

Q=(m)(c)(change in temp)

Q=Power(time)

Q=(m)(c)(change in temp)

electronic signals

Info sent as patterns in the controlled flow of electrons thru a circuit

vacuum tube

change alt current to direct current, increase signal strenght, turn currents on or off

semiconductors

conduct currents only under certain conditions

Diodes

combine n-type and p-type

transistors

3 layers used as a switch

integrated circuit

thin slice of silicon that contain solid state components