When one tuning fork is struck and placed near another of the same frequency, the second fork begins to vibrate without being struck.

1. Place two tuning forks of the same pitch on a table, with one mounted on a wooden resonance box.
2. Strike the free tuning fork gently to produce a clear tone.
3. Hold it near the mounted tuning fork for a few seconds.
4. Stop the vibration of the first fork by lightly touching it.
5. Listen for the sound continuing from the mounted fork, which is vibrating sympathetically.
6. Optionally, repeat the demonstration with a string instrument, showing how strings vibrate in sympathy when a matching tuning fork is struck nearby.

Sympathetic Resonance - Michael McPeck:

📄 Tuning Fork - Adjustable Sympathetic - Set of 2 (also describes procedure) - Modern Teaching Aids: https://www.teaching.com.au/product/tuning-fork-8211-adjustable-sympathetic-8211-set-of-2?srsltid=AfmBOoqMOjT1E66iwWPgPP7BCzOSgFsNBDss8v_GECKzskpLBqTh-xqt

• Try tuning forks tuned to different intervals (octave, fifth, third) to compare resonance strength.
• Demonstrate with a guitar or piano: strike a tuning fork near a string of the same pitch and listen for the string vibrating.
• Use multiple tuning forks to show selective resonance - only the one with the same frequency responds.
• Use an analogy for earthquake waves propagating through the Earth's crust

• Strike tuning forks against a rubber striker or padded surface, not hard objects, to prevent damage.
• Handle tuning forks carefully; avoid dropping them on hard surfaces.

• Why does the second tuning fork vibrate without being struck?
• Why is the effect strongest at unison and octaves compared to other intervals?
• How does sympathetic resonance enhance the sound of string instruments like pianos or sitars?
• What factors determine whether two objects can resonate sympathetically?
• Can sympathetic resonance occur outside of music (e.g., in bridges or buildings)?