Basic Circuitry

Basic Circuitry

Mark Reymund E. Balderama, RRT, MSPH

Objectives

  • Define potential difference, current, and resistance.

  • Describe the laws of electrostatics, different electrical circuits, and demonstrate proper grounding procedures.

Definition of Terms

  • Electricity: Form of energy created by the activity of electrons and subatomic particles in motion.

  • Electrification: Process of adding or removing electrons from a substance.

  • Electrified Object: Object with too few or too many electrons.

  • Electric Current: Flow of electrons.

  • Electric Field: Force exerted on charged ions by electrodes that cause particle movement.

  • Electrical Energy: Work done when a charge moves through an electric potential.

  • Electrode: Electrical terminal or connector.

Electrostatics

  • Electrostatics: Study of electromagnetic phenomena in stationary conditions.

  • Coulomb's Law: Force between two point charges is proportional to their magnitudes and inversely proportional to the distance squared.

  • Electric Potential: Work needed to move a unit charge without acceleration.

Electrodynamics

  • Electrodynamics: Study of charged bodies in motion and varying electric and magnetic fields.

  • Electric Circuits: Path through which electrical current flows, may be closed or open.

  • Electric Power: Rate of energy transfer in an electric circuit; unit is watt (J/s).

Laws of Electrostatics

  • Repulsion-Attraction: Like charges repel; unlike charges attract.

  • Distribution: Charges reside on the surface of a conductor.

  • Concentration: Charges concentrate at the sharpest point of a conductor.

  • Movement: Only negative charges move in solid conductors.

Electric Potential

  • Amount of work needed per unit of charge in an electric field, also called voltage.

  • Higher voltage equals greater potential to perform work.

Current vs Voltage

  • Voltage: Difference in electric potential between two points.

  • Current: Rate of flow of electric charge.

  • Types:

    • Direct Current (DC): Unidirectional flow; examples include batteries.

    • Alternating Current (AC): Direction of flow changes periodically; used in household electricity.

Magnetism

  • A fundamental property of matter; created by moving charged particles.

  • Magnetic Field Lines: Represent the intensity and direction of a magnetic field.

Laws of Magnetism

  • Like poles repel; unlike poles attract.

  • Every magnet has a north and south pole.

  • The force decreases with the square of the distance between magnets.

Key Concepts

  • Magnetism: Properties of matter related to charge and motion.

  • Magnetic Domain: Collection of aligned atomic magnets.

  • Magnetic Induction: Process of making a material magnetic.

  • Measured in tesla (T) or Gauss (G); 1T = 10,000 G.