======Tuning Fork and Ping Pong Ball======


<WRAP right box>
**Materials: **{{$demo.materials_description}}\\
**Difficulty: **{{$demo.difficulty_description}}\\
**Safety: **{{$demo.safety_description}}\\
\\
**Categories:** {{$demo.categories}}
\\


**Alternative titles:** Seeing Sound Vibrations with a Ping Pong Ball
</WRAP>

====Summary====                   
{{$demo.summary}}



====Procedure====  
  - Attach a ping pong ball to a piece of string.  
  - Suspend the string so the ball hangs freely (use a clamp stand or tape the string to a desk).  
  - Strike a tuning fork gently on a firm but padded surface, such as a rubber mallet or the side of a desk.  
  - Hold the vibrating tuning fork close to the suspended ping pong ball.  
  - Observe how the ball moves when it is touched by the vibrating tuning fork.



====Links==== 
Ping Pong Ball vs Tuning Fork - Another Sound Wave Demo - Ed Reeves: 
{{youtube>uVC4pIdLSNM?}}\\


📄 Seeing sound vibrations - The Ogden Trust: [[https://www.ogdentrust.com/wp-content/uploads/2021/09/Purposeful-practical-seeing-sound-vibrations.pdf]]\\

====Variations====
  * Test what happens when you strike the tuning fork with different amounts of force (lightly, medium, hard).  
  * Try changing the mass of the ping pong ball by taping small amounts of Blu Tack to it and observe how this affects its movement.  
  * Compare how balls of different materials (such as Styrofoam or cork) react to the tuning fork vibrations.



====Safety Precautions====
  * Do not hit the tuning fork on hard surfaces like metal or stone, as this may damage it.
  * Make sure the ping pong ball is suspended securely so it does not fly off.




====Questions to Consider====
  * Why does the ping pong ball move when touched by the tuning fork? (Because the vibrating prongs transfer energy to the ball.)  
  * What happens if you strike the tuning fork harder? (It produces larger vibrations, causing a louder sound and greater ball movement.)  
  * Why does the ball eventually stop moving? (Because energy is lost to the air and friction, so the vibrations fade.)  
  * Why is a ping pong ball used instead of a tennis ball? (It is very light, so even small vibrations can move it.)  
  * How does the length of a tuning fork’s prongs affect its pitch? (Shorter prongs vibrate faster, producing higher-pitched sounds, while longer prongs vibrate slower, producing lower-pitched sounds.)