Certainly! Here is the explanation of the science behind sound differences in instruments and string telephones in English.
1. Violins vs. Cellos: Why is the "Pitch" Different?
The pitch (frequency) of a stringed instrument is primarily determined by the length, thickness, and tension of its strings.
String Length: Longer strings vibrate more slowly, creating a lower pitch. Since a cello is much larger than a violin, its strings are longer, resulting in deeper sounds.
String Thickness (Mass): Thicker and heavier strings require more energy to move and vibrate more slowly. Even on a violin, the thickest string (the G string) produces the lowest note.
Body Resonance: To amplify low-frequency sounds, you need a large space. A violin’s small body cannot effectively amplify deep bass, whereas a cello’s large hollow body is designed specifically to resonate with lower frequencies.
2. String Telephones: Why do Materials Change the "Tone"?
In a string telephone experiment, the difference in sound between sewing thread, kite string, and wire is caused by the material's elasticity (stiffness) and surface structure.
① Sewing Thread (Fine Cotton)
Characteristics: Very thin and lightweight.
Sound Quality: It transmits high-pitched sounds relatively well, but because it has very little mass, the sound energy fades quickly. It often results in a delicate, "scratchy" sound.
② Kite String (Thick Cotton/Twine)
Characteristics: Thicker than sewing thread and often has a "fuzzy" surface.
Sound Quality: The thickness allows it to carry lower tones better than thin thread. However, the tiny fibers on the surface create air resistance and absorb vibrations, leading to a "muffled" or softer sound.
③ Wire (Metal)
Characteristics: Extremely stiff and high in density.
Sound Quality: Sound travels much faster through metal than through fiber. Metal also has very low "damping" (meaning it doesn't soak up the vibration). This results in a very clear, sharp, and "metallic" sound that can travel much further than string.
3. The Mystery of "Overtones"
Even if the pitch is the same, a violin sounds different from a cello because of Overtones (Harmonics).
Sound is not a single clean wave; it is a combination of a fundamental frequency mixed with many smaller, faster vibrations.
Hard Materials (Wire): Preserve high-frequency overtones, making the sound bright and sharp.
Soft Materials (Cotton String): Absorb high-frequency overtones, making the sound warm and round.
Summary
Pitch is determined by the physical dimensions (length and thickness).
Timbre (Tone Quality) is determined by how the material properties transmit or absorb different frequencies of vibration.
📋 この回答をコピーする
Would you like to explore the mathematical formulas for string vibration, or perhaps see more examples of how different materials affect acoustics?
