Question

The strings that play the lowest notes on a piano are made of thick steel wire wrapped with a spiral of heavy copper wire. The copper wire doesn't contribute to the tension in the string, so what is its purpose?

Answer 1

The heavy copper wire wrapped around the steel strings of a piano increases the strings' mass, allowing for lower-frequency notes without drastically increasing the strings' length or looseness.

Step-by-step explanation:

The thick steel wire strings that play the lowest notes on a piano are wrapped with a spiral of heavy copper wire. While the copper wire does not contribute to the tension of the string, it is crucial for another property: increasing the mass of the string. This additional mass allows the strings to vibrate more slowly, resulting in lower-frequency notes that are essential for the depth and richness of a piano's sound. Without the copper wire, the strings would need to be much longer or much looser to produce the same pitches, which is not practical given the piano's size constraints.