Electricity, Magnetism, Electromagnetism

Smallest unit of electrical charge is the…

electron

electrons are measured with…

coulomb

1 coulomb =

6.3 × 10¹⁸ electron charges

Electrification

too few or much electrons (protons unmoved)

Electrostatics means…

study of electric charges in stationary form

3 methods of electrification

• friction

• contact

• induction

friction

like rubbing fur on a rod

contact

friction-charged body comes in CONTACT with another object

induction

arranged electrons on uncharged object in presence of charged object

when object is electrically charged, it’ll manifest…

an electrical field or force around i

There’s how many laws of electrostatics?

4

1st Law of Electrostatics

different charges attract, same repel

2nd Law of Electrostatics

electrons travelon outside of a conductor (wire)

3rd Law of Electrostatics

electric charges are concentrated on the sharpest curvature of a conductor 

4th Law of Electrostatics

Electrostatic force is:

• Directly proportional to the product of charges

• Inversely proportional to the square of the distance

Coulomb’s law is…

EF = k(Q₁Q₂)/d²

An object that’s electrically charged has the…

potential energy to do work

Measure x-ray energy in…

volts/kilovoltage potential (kVp)

electrodynamics is…

study of electricity in motion

What is currents?

the flow of electricity or electrons

how to measure currents?

amperage (A)/ mAs

conductor vs insulator

allows electrons to flow vs inhibits electron flow

Ex of conductors…

metal, gold, copper, silver, water

Ex of insulators…

wood, rubber

semiconductors are…

conduct or insulate under certain conditions, like silicon

superconductor is…

for allowing electron flow without resistance like titanium

circuit

allows electron flow from a generated source through multiple parts and back to source again 

Ammeter

measures electron flow

3 Parts of a Circuit

1. current

2. potential differences

3. resistances

Current is measured in…

amperes (A)

Potential differences is measured in…

volts (V)

Resistances (R) is measured in…

ohms (Ω)

What is resistance?

anything that opposes or hinders electron flow

What 4 aspects influence Resistance (R)?

1. length of conductor

2. cross-section of wire

3. material wire is composed of

4. wire temp

Ohm’s law =

Voltage (V) = Current (I) x Resistance (R)

Power is…

work done per unit of time, measured in watts (W)

Power (P) =

Current (I) x Voltage (V) OR I² x Resistance (R)

What electrical symbol is this? 

single cell

What electrical symbol is this? 

battery

What electrical symbol is this? 

connecting wire

What electrical symbol is this? 

resistor

What electrical symbol is this? 

switch (open)

What electrical symbol is this? 

switch (closed)

What electrical symbol is this? 

transformer

2 types of circuits

• series

• parallel

Series vs Parallel Circuits - difference in path?

Series has 1 path of electron flow vs Parallel has 2+

Series vs Parallel Circuits - difference in interruption reaction?

in a Series, electron flow stops if any part is interrupted vs in a Parallel, electrons can flow through other branches of circuit

Series circuit is rep by…

R_t = R₁ + R₂ + R₃… or sub R with V, while Amperage remains constant in circuit

Parallel circuit is rep by…

note: voltage remains constant

2 types of currents

alternating vs direct

Difference in Alternating vs Direct currents

AC allows electron flow to switch directions (like in an AC generator) vs Direct lets electron flow in one direction (like batteries)