Spring. Ext.Steel 15mm dia 55mm length

• Dimensions: With a 15mm diameter and an overall length of 55mm, these are medium-sized springs that are easy for students to handle and observe from a distance.
• Coiled Length (20mm): This refers to the active part of the spring where the energy is stored. The remaining 35mm of the "overall length" typically consists of the extended loops or hooks at each end for easy attachment to mass hangers and retort stands.
• Wire Gauge (0.7mm): This relatively thin wire ensures a lower spring constant (k
  
  ), meaning the spring will show significant, measurable extension even with small weights (like 10g or 20g masses), which is ideal for precise classroom data collection.

• Hooke’s Law: Students measure the "extension" (total length minus original length) as they add incremental masses. Plotting Force vs. Extension should yield a straight line, demonstrating that F = kx
  
  
  .
• Elastic Limit: Older students can test at what point the spring becomes permanently "stretched" and fails to return to its original 20mm coiled length.
• Simple Harmonic Motion (SHM): By hanging a mass and seting it in motion, students can calculate the period of oscillation and see how it relates to the mass and the spring constant.

Specifications