# 9. Wave Equation, Standing Waves, Fourier Series | Summary and Q&A

34.4K views
April 18, 2018
by
MIT OpenCourseWare
9. Wave Equation, Standing Waves, Fourier Series

## TL;DR

Coupled oscillators work together to create wave phenomena and can be described using wave equations.

## Key Insights

• 💦 Coupled oscillators work together to create wave phenomena.
• 👋 Wave equations describe the behavior of coupled oscillators as waves.
• 📳 Boundary conditions and initial conditions can be used to determine the properties of normal modes.

## Transcript

The following content is provided under a Creative Commons license. Your support will help MIT OpenCourseWare continue to offer high quality educational resources for free. To make a donation or to view additional materials from hundreds of MIT courses, visit MIT OpenCourseWare at ocw.mit.edu. YEN-JIE LEE: So welcome back, everybody, to 8.03. Happy... Read More

### Q: How are coupled oscillators related to wave phenomena?

Coupled oscillators work together to create wave phenomena. Many objects oscillating in sync can create a wave.

### Q: How are wave equations used to describe coupled oscillators?

Wave equations are used to describe the behavior of a system of coupled oscillators. By solving these equations, we can understand the wave properties of the system.

### Q: How do boundary conditions help determine normal modes?

Boundary conditions restrict the possible shapes and amplitudes of normal modes. By imposing boundary conditions, we can determine the specific normal mode shapes that are allowed within a system.

### Q: How can initial conditions be used to determine amplitudes and phases of normal modes?

By considering the initial conditions of a system, such as the initial position and velocity, we can determine the amplitudes and phases of normal modes using integration and orthogonality of sine functions.

### Q: What is the general solution to the wave equation?

The general solution to the wave equation is a linear combination of all possible normal modes, each with their own amplitude and phase.

## Summary & Key Takeaways

• Coupled oscillators work together to create wave phenomena and can be described using wave equations.

• Solving wave equations involves using boundary conditions to determine the shape and amplitude of different normal modes.

• The amplitude and phase of each normal mode can be determined by initial conditions and orthogonality of sine functions.

• The general solution to the wave equation is a linear combination of all possible normal modes.