| Arrangement in series: | Arrangement in parallel: |
| Extension = x × number of spring Stiffness decreases Spring constant = k/number of spring | Extension = x ÷ number of spring Stiffness increases Spring constant = k × number of spring |
Factors Affecting the Stiffness of Spring
| Stiffer | Less stiff | |
| Material type of spring (A steel spring is stiffer than a copper spring) |  |  |
| Diameter of wire of spring (The greater the diameter of the wire, the stiffer the spring) |  |  |
| Diameter of the spring (The smaller the diameter of spring, the stiffer the spring) |  |  |
| Length of the string (Shorter spring is stiffer) |  | |
