1. Tension: The higher the tension of the string, the higher the pitch. This is because the tension increases the restoring force on the string, which causes it to vibrate faster. Violins have higher string tension than basses, which allows them to produce higher pitches.
2. Length: The shorter the string, the higher the pitch. This is because a shorter string has less mass to vibrate, so it can accelerate and decelerate more quickly. Violins have shorter strings than basses, which allows them to produce higher pitches.
3. Mass: The heavier the string, the lower the pitch. This is because a heavier string has more mass to vibrate, so it takes more force to accelerate and decelerate it. Violins have lighter strings than basses, which allows them to produce higher pitches.
In summary, violins can play higher pitches than basses because they have higher string tension, shorter strings, and lighter strings.