Precise measurement reveals just how slightly temperature shifts a vibration rate. You cool a 640 Hz tuning fork in a freezer and heat it in stages to test five temperatures: 0°C, 25°C, 50°C, 75°C, and 100°C. At each step you tap the fork and record its frequency with a sound sensor and scope. At 0°C it reads 641.6 Hz. By 100°C it drops to 639.9 Hz — a small but consistent change.

Some thermal changes are too subtle to notice without precise instruments. A 640 Hz tuning fork reads 641.6 Hz at 0°C, but as it warms the frequency edges downward. By 100°C it has dropped to 639.9 Hz — less than 2 Hz across the full range. At each temperature, an infrared thermometer confirms the reading while a sound sensor and scope capture the frequency. The result shows that even small temperature changes alter how the metal vibrates.