Electrical Basics

Electrical Basics

Electric Charge

• Electric charge is a fundamental property of matter
• There are two types of electric charge: positive and negative
• Like charges repel each other, while opposite charges attract each other

Electric Current

• Electric current is the flow of electric charge (e.g. electrons)
• Measured in amperes (A)
• Current flow is from positive to negative terminals

Voltage (Electric Potential Difference)

• Voltage is the potential difference between two points in a circuit
• Measured in volts (V)
• Can be thought of as the "pressure" that drives electric current

Resistance

• Resistance is the opposition to electric current flow
• Measured in ohms (Ω)
• Depends on the material, length, and cross-sectional area of a conductor

Ohm's Law

• Relates voltage, current, and resistance: V = I × R
• Can be rearranged to solve for any of the three variables

Conductors and Insulators

• Conductors: materials that allow electric current to flow (e.g. copper, aluminum)
• Insulators: materials that resist electric current flow (e.g. rubber, glass)

Series and Parallel Circuits

• Series circuit: components connected one after the other
  • Current is the same throughout the circuit
  • Voltage is divided among components
• Parallel circuit: components connected between the same two points
  • Voltage is the same across each component
  • Current is divided among components