Imagine a jump rope! When you flick one end, the wave travels to the other end. What happens when it reaches the end depends on if it's tied (fixed) or free!

• Fixed End
  • Like when one end of your jump rope is tied to a pole!
  • When the wave reaches this end, it reflects and goes π rad out of phase with the incoming wave.
  • What's π rad? Think of flipping a pancake upside down! 🥞
  • 🎉 Key Point: The displacement at the fixed end is always zero. So, the reflected wave must

• Move in the opposite direction.
• Be inverted compared to the incident wave (that pancake flip!).
• Have the same shape as the original wave.
• Free End
  • Like when both ends of your jump rope are in your hands!
  • Reflected wave is like the original wave and doesn't invert. It's as if the rope waves back, saying, "Hi!" 👋
• Models—Neither Fixed nor Free
  • Imagine a beach, with waves coming in and changing intensity based on how deep or shallow the water is. That's how waves behave between high and low-density mediums.
  • Fun Fact: When you play a guitar 🎸, the tiny wave on the string hits a fixed end (bridge). This vibration, even though minimal, goes through the body of the guitar and sends sound waves into the air—making sweet melodies! 🎶

When you pluck a guitar string, the tiny wave moves until it meets the bridge (fixed end). Some of its energy is transferred to the bridge, which makes the body of the guitar vibrate. Those vibrations become sound waves that fill the room with music! So next time you hear a guitar, remember the waves!