12 Electricity

Electron flow (I) How much charge (how many electrons) pass through certain point in circuit per unit time Quantity measured in Amperes Body current = ion movement

Stored charge Substance ability to store a charge

How electricity generated

I = V / R Analogous to Q = ΔP/R or BP = CO x SVR

Electromotive force (EMF) or force that pushes electrons through resistance Electrical charge potential difference directly proportional to electron flow (electric current) Driving pressure P1 - P2 Measured in Volts

Opposition force to electron flow Flow inversely proportional to resistance Measured in Ohms

Electric charge measure unit 1e¯ = 1.602 x 10^-19 1 Coulomb = 6.24 x 10^18 electrons 1 Coulomb e¯/sec = 1 Amp

Ampere (Amp) measures current 1 Amp = charge movement carried by 6.24 x 10^18 electrons passing a certain point in 1 second 1 Amp = 1 Coulomb electric charge movement

Current = voltage/resistance E = I x R Electromotive force (E) = voltage E = I x Z Impedance (Z)

Represented by Z Resistance to current flow that changes w/ frequency Power supply frequency at constant 60Hz Impedance & resistance are interchangeable High impedance = low current flow Low impedance = high current flow

Power unit (work/time) Joules/second Electrical power measurement W = V x I

Watt-second = work = energy Work = mass x acceleration x distance kg x m/s^2 x m or 1 Joule

Force x distance (displacement) Force = mass x acceleration Measured in Joules

Kinetic = (mass x velocity^2) / 2 Potential = mass x 9.81m/s^2 x height

Measured as Watts in electrical circuit I x V

Permits e¯ flow Current = e¯ flow through conductor

Insulators Tightly bound electrons that do not permit e¯ flow Ex: glass, rubber, plastic, dry wood, pure water

Direct current e¯ flow always in the same direction Ex: batteries

Alternating current e¯ flow reverses direction (oscillates) at regular intervals Oscillating frequency measured in cycles per second (Hertz or Hz) Ex: electric company

Substance ability to store a charge

Electrical device used to shore electric charge Basic design - 2 parallel conducting plates separated by insulating layer called dielectric

Force field that consists both electric & magnetic components Resulting from electric charge motion & containing definite amount electromagnetic energy Electrons flow through wire induce a magnetic field around When wire coiled repeatedly around an iron core → amplifies the magnetic field Dual nature r/t electricity & magnetism - Where there’s an electric current there are also magnetic waves - Where there are changing magnetic waves there’s an electric current Able to do work

e¯ flow via wire induce magnetic field surrounding When wire coiled repeatedly around an iron core this will increase the electromagnetic field to move e¯ Ex: wireless charging

Battery source Metal bar w/ coiled wire Fixed magnets Opposing magnetic fields repel e¯ to rotate the metal bar