Waves transport energy, not matter, across space.

A wave stores energy in the medium and moves that energy along as the disturbance travels. The key is separating energy flow from medium motion.

• Energy in oscillating elements of the medium
• Energy moves even if matter doesn’t
• Where energy is largest in a wave
• Qualitative dependence on amplitude

Power is the rate of energy transfer. Wave power depends on how much energy passes a point per unit time.

• Power as energy per time
• What increases transmitted power
• Amplitude sensitivity (conceptual)
• Role of medium properties

Intensity is power per area. It is the natural measure for waves spreading out, especially in 2D/3D propagation where energy distributes over a surface.

• Intensity as power per area
• Why spreading reduces intensity
• Interpreting “loudness” and “brightness”
• Units and scaling reasoning

Real waves can lose energy to internal friction, viscosity, or other dissipative effects. Attenuation describes how amplitude and intensity decrease with distance.

• Dissipation mechanisms (conceptual)
• Amplitude vs intensity decrease
• Separating spreading from absorption
• Why attenuation matters in applications

Practice reasoning about energy flow, converting between power and intensity, and explaining why waves weaken in real media.

• Energy-transport concept checks
• Power interpretation problems
• Intensity and area scaling drills
• Attenuation vs geometric spreading questions
• Exam-style energy-in-waves sets