Overview

This topic covers the nature of waves and the behavior of light and electricity. It explores the fundamental properties of wave motion, the electromagnetic spectrum, electrical circuits, and how energy is transmitted through various media.

Key Concepts and Principles

• Waves: Disturbances that transfer energy through a medium. Types include mechanical (sound, water) and electromagnetic (light, X-rays).
• Wave Properties: Frequency (Hz), wavelength (λ), amplitude, and speed. Formula: speed = frequency × wavelength
• Sound Waves: Longitudinal mechanical waves that require a medium to travel. Speed depends on the medium.
• Light: An electromagnetic wave that travels in a vacuum. Behaves as both a wave and a particle (photon).
• Electromagnetic Spectrum: Includes radio waves, microwaves, infrared, visible light, ultraviolet, X-rays, and gamma rays — arranged by wavelength and frequency.
• Reflection and Refraction: Light bounces off surfaces (reflection) or bends when passing through different media (refraction).
• Electricity: Movement of electric charge through a conductor, measured in amperes (A).
• Current and Voltage: Current is the flow of charge; voltage is the electrical potential difference. Related by Ohm's Law: V = IR
• Circuits: Closed paths that allow electricity to flow. Include components like resistors, batteries, switches, and bulbs.
• Static Electricity: Buildup of electric charge on an object. Often caused by friction and results in electric discharge.

Quick Tip