Basic Electrical Engineering (ELEN 016)

Fundamentals of Electricity

• Module Title: Basic Electrical Engineering (ELEN 016)
• Professor: Engr. Jomar J. Daciles, REE, RME, SO2
• Institution: Polytechnic University of the Philippines

Objectives

• Explain electricity and related electrical terminology
• List and describe sources of electricity
• Differentiate between insulators and conductors

What is Electricity?

• Electricity is a form of energy from charged particles (electrons/protons).
• It can be static (accumulation of charge) or dynamic (current).
• Electricity can also be a state of excitement or thrilling feeling.

Background: Thales of Miletus

• (624-546 BCE) - early contributor to philosophy, mathematics and astronomy
• Credited with early observations of static electricity; experimented with amber
• Noted rubbing amber (fossilized resin) with fur can attract light objects (feathers, straw).
• This is one of the earliest observations of static electricity and important for later scientific discoveries.

Background: William Gilbert

• (1544-1603) - pioneering figure in electricity and magnetism
• Laid groundwork for understanding static electricity.
• Demonstrated various materials producing an attractive force through experiments.
• First to recognize that rubbing certain substances creates static electricity
• Coined the word "electricity" based on the Greek word for amber (electron).
• Significance: His work is foundational for the development of electrical sciences.

Static Electricity

• Electricity that is at rest
• Electric Charge: A quantity of electricity held in an object
• Two types of electric charge: Positive and Negative
• Neutral Charge: Equal amounts of positive and negative charges

Electrical Charge

• Positive charge: Associated with protons in the atomic nucleus.
  • repels other positive charges, attracts negative charges
• Negative charge: Associated with electrons orbiting the atomic nucleus.
  • repels other negative charges, attracts positive charges
• Neutral charge: Equal number of protons and electrons in a substance.

Electrical Charge (Protons and Electrons)

• Protons: Positively charged particles found in the atomic nucleus
• Electrons: Negatively charged particles orbiting the atomic nucleus
• Electrostatic Repulsion: Like charges repel each other
• Electrostatic Attraction: Opposite charges attract each other

Overview of Electricity

• Electricity is made up of negatively and positively charged elements, which are electrons and protons respectively
• Electric current is the directed movement of free electrons.

Electrical Terminologies

• Circuits: A closed path for current flow, including a source, conductor, and load
• Current: The flow of free electrons in a circuit, measured in Amperes (A)
• Voltage: Potential difference in charge, measured in volts (V); the force to move charge.
• Resistance: The opposition to current flow in a substance, measured in ohms (Ω)

Conductors and Insulators

• Conductor: Materials that allow electric current to flow easily (metal).
• Insulator: Materials that resist electric current flow (rubber, porcelain, plastic).

Third Party Disturbances

• Heat, Magnetism, Chemical reaction, Photon Energy, Friction

Current (Electric Current)

• Directed flow of free electrons

Methods to Have Free Electron

• Valence electrons: outermost shell electrons in an atom.
• Insulators: Greater number of valence electrons than 4.
• Semi-conductors: Equal to 4 valence electrons.
• Conductors: Less than 4 valence electrons

Voltage (V)

• Force that moves charge, measured by the work done in moving a charge through an electric field. The quantitative expression of potential difference in charge between two points in an electrical field.
• Formula: V = W/Q
  • Voltage (V) = Work (W) done divided by Charge (Q)

Sources of Electricity

• (no specific sources listed in the provided text)

Types of Voltage

• Direct Current (DC)
• Alternating Current (AC)

Direct Current (DC)

• One-directional flow of current, Negative to Positive
• Example: A battery

Direct Current Example

• Solar panels converting sunlight into electricity
• Deep-cycle batteries store power
• Inverter converts DC to AC power
• Using a power bank

Alternating Current (AC)

• Reverses its direction periodically.
• Example: Power lines in most homes, commonly used for homes.

AC advantage over DC

• Easier and cheaper production
• Distributing AC over longer distances is cheaper, higher voltage distribution is simpler
• More efficient

Example: Rectifier

• Device that converts AC to DC Voltage

Power Generation

• (diagram/illustration provided)

This quiz covers the fundamentals of electricity, including key terminology, sources of electricity, and the distinction between conductors and insulators. Students will also explore the historical contributions of Thales of Miletus to our understanding of static electricity. Evaluate your knowledge on these essential concepts in electrical engineering.