The stretch of a spring in millimeters refers to the distance that the spring is extended or compressed from its original, relaxed length. To measure it, you can use a ruler or caliper. The formula for calculating the stretch of a spring can be expressed using Hooke's Law, which states:
\[ F = k \cdot x \]
Where:
- \( F \) is the force applied to the spring (in newtons),
- \( k \) is the spring constant (in newtons per millimeter or similar units),
- \( x \) is the stretch or compression of the spring (in millimeters).
If you have a specific spring stretch measurement or additional information about the spring, please provide that for more detailed assistance!