Understanding Electricity and Electric Force

Fundamental Forces and Electricity

• Humans understand four fundamental forces: gravitation, electromagnetic, strong nuclear, and weak nuclear.
• Electric force is essential in generating and using electricity in modern life.

Basics of Atoms

• Everything is made up of atoms.
• Atoms contain a nucleus (protons and neutrons) and electrons orbiting the nucleus.
• Protons: Positive charge
• Electrons: Negative charge
• Neutrons: No charge
• Number of protons determines the element (e.g., 1 proton = hydrogen, 6 protons = carbon).
• Stable atoms have equal protons and electrons, resulting in neutral charge.
• Ionized atoms: Positively charged (more protons) or negatively charged (more electrons).

Electron Shells and Valence Electrons

• Electrons orbit in different energy levels (shells).
• Shells closer to the nucleus hold fewer electrons (2 in the first shell, 8 in the second, etc.).
• Valence electrons: Electrons in the outermost shell, easily pushed out by force.

Electricity and Electron Movement

• Moving electrons between atoms create electricity.
• Conductors (e.g., copper, silver) have loosely held valence electrons, making electron movement easier.
• Insulators (e.g., plastic, rubber, glass) hold electrons tightly, preventing electrical flow.
• Rubbing or touching objects can transfer electrons.
• Static electricity example: Walking on a carpet and then touching a metal object.

Simple Electric Circuit

• Battery: Acts as a pump, creates potential difference (excess electrons on one side).
• Conductors (e.g., copper wire) facilitate electron flow.
• Electrons move from negative to positive terminal, producing current when circuit is closed.
• Light bulb: Tungsten filament resists electron flow, heats up, and glows.

Electric Current

• Current: Flow of electrons through a conductor, measured in amperes (1 ampere = 1 coulomb of electrons per second).
• Example: 1 coulomb = 6.28 billion billion electrons.
• Analogy to water flow: Liters of water passing a point per minute.

Voltage

• Voltage (electric potential difference): Pushes electrons in a circuit.
• Battery example: One end with excess electrons (negative), the other with positive charge.
• Gravitational analogy: Potential energy difference when lifting a ball.
• Voltage measured in volts (1 volt = 1 joule/coulomb).
• Higher voltage increases current; lower voltage decreases current.
• Appropriate wire thickness is necessary for different voltages to prevent overheating and damage.

Safety and Future Prospects

• Electrical safety is crucial to prevent accidents (over 1.2 million accidents annually).
• Proper usage of electric force can advance human civilization.