How Electricity Works

Introduction

• Speaker: Paul from TheEngineeringMindset.com
• Topic: Essential knowledge of electricity for engineers.

Basic Structure of Atoms

• Everything is made of atoms, including materials used in engineering.
• Components of an Atom:
  • Nucleus:
    • Contains neutrons (no charge) and protons (positively charged).
    • Neutrons and protons are heavier than electrons.
  • Electrons:
    • Negatively charged, orbit the nucleus in orbital shells (like satellites).
    • Electrons travel at nearly the speed of light.
    • The outermost shell is called the valence shell.

Conductors and Insulators

• Conductors:
  • Atoms with loosely bound electrons that can flow (e.g., metals).
• Insulators:
  • Atoms that do not allow electron flow (e.g., glass, rubber).
  • Insulators surround conductors to keep users safe from electric shock.

Electric Current and Circuits

• Electric Current:
  • Flow of electrons in a closed circuit.
• Closed Circuit:
  • Electrons flow between positive and negative terminals of a power source.
• Open Circuit:
  • Electrons cannot flow.

Voltage and Current

• Voltage:
  • The pushing force of electrons within a circuit (analogous to water pressure).
  • Measured in volts (1 volt = 1 joule per coulomb).
• Current:
  • Measured in Amps (1 Amp = 1 coulomb per second).
  • A coulomb consists of approximately 6.242 x 10^18 electrons.

Resistance

• Resistance:
  • Restriction to the flow of electrons, varies by material and temperature.
  • Measured using resistors in circuits to control current flow.

Electromagnetic Fields

• Wrapping a wire in a coil intensifies magnetic fields, affecting electron movement.
• Electromagnets:
  • Created by wrapping coils around an iron core.
• Induction:
  • A magnetic field passing across a coil induces a voltage, causing current to flow.

Transformers

• Transformer:
  • Uses coils to induce voltage, allowing for voltage increase or decrease.

Capacitors

• Capacitors:
  • Store and release electric charge, providing temporary power.
  • Separate positive and negative charges across two plates.

Types of Current

• Alternating Current (AC):
  • Current flows back and forth, common in household electricity.
• Direct Current (DC):
  • Current flows in one direction, typical from batteries and handheld devices.
• Conversion between AC and DC is necessary for the use of solar panels and charging devices.

Conclusion

• Importance of understanding electricity for engineering.
• Encouragement to subscribe and explore further resources.
• Q&A invitation in the comments.