What did the baby light bulb say to the mommy light bulb? "I love you watts and watts!"

  

  

• Law of Electrostatics: like charges repel; unlike charges attract  

Electric Charge – general information on positive and negative charges

Static Electricity – static electricity and the movement of charges

• Conductor: material that transfers charges easily
• Insulator: A material that does not transfer charge easily  
• Semiconductor: somewhere between 1 and 2
• Superconductor: some metals become perfect conductor below certain temperatures
• Ways to charge:   
  • By conduction: contact between a charged and neutral object (results in 2 objects of the same charge)  
  • By induction: no contact between a charged and neutral object (results in 2 objects of the opposite charge)  

Electrical Conductors – additional information on conductors

Electrical Insulators – additional information on insulators

• Coulomb’s Law 
• Coulomb Constant – 8.9875 x 10⁹ Nm²/C²

 Coulomb's Law – more on Coulomb’s Law and electric charges

• Electric Field     
  

o       E – electric field (N/C) 

• Magnitude: intensity at a point in space defined as force per unit charge (N/C) that would be experienced by any test charge placed at that point 
• Magnitude of Electric Field       E = kq                

                                                                                r²

• Field Lines – used to visualize the electric field 
• Electrostatic Equilibrium - no net motion of charge occurs within a conductor

 

 

• Electric Potential U = qV
  • Volts – (J/C)  
• Electric Potential V = kq  

                  r

• Potential Difference V = Er  

Voltage for Multiple Charges – more on calculating electric potential

• Capacitor: two conducting surfaces separated by an insulating material; stores charge 
• Capacitance
• Energy Stored                  
                           
• Capacitance with Dielectrics  
  
  • E_o – Dielectric constant (8.854 x 10^-12)

Capacitance – more information on capacitance

How Capacitors Work – additional information on how capacitors work

• Electric Current  
• Ohm’s Law 
  • V – volts; I – electric current; R – resistance  
  • Resistance – Ohm (V/A)
• Resistivity  

•  p – resistivity (ohm-meter)
• Resistance and Resistivity
  • Factors that affect resistance:

1. Length: longer materials have greater resistance

2. Cross-Sectional (surface) area: Larger the area offers less resistance

3. Temperature: higher temperatures have higher resistance

4. Kind of Material

• Energy and Power

Resistance and Resistors – additional information on resistance and resistors

Currents – general information about electrical currents

• In series – one path for current to flow
• In parallel – more than one path for the current to flow

Series and Parallel Circuits – additional information on series and parallel circuits

Series vs Parallel Circuits – the differences between the two types of circuits

All About Circuits – example problems and formulas related to circuits

Formulas for Circuits – contains all formulas for calculating voltage, current, and resistance  

Resistance Applet - applet demonstrating the principle of resistance

 

  

 

• Magnetic Force                     
  • q – charge (C); v – velocity (m/s); B – magnetic field (T)  
• Velocity    v = EB
  • E – field  
• Torque   I B L sin(Ө)
  • I – current; B – magnetic field (T); L – length (m)  
• Magnetic Field   2π(B r) = μ_oI
  • Permeability - μ_o - 4π x 10^-7

Magnetic Formulas – any magnetic field formula you would ever need

Right Hand Rule  - how to learn and apply the right hand rule