Tension Protractor

SKU: ME-6855 Category: Tag:



  • Conveniently measure both Tension and Angle
  • Large Scale for Viewing Demonstrations
  • Zero-Adjust for Torsion Spring Scale
  • Built-In Rod Clamp for quick horizontal or vertical mounting

The Tension Protractor is a spring scale and a protractor integrated into one device. Perfect for static equilibrium experiments, the rotary dial indicates the tension in the string and the angle is read where the string passes over the degree scale on the outer ring. Since the Tension Protractor is supported on a rod, it has an advantage over other spring scales which tend to weight down the string, changing the angle.

The string is wrapped once around a small pulley which is spring loaded. The torsion spring scale is carefully calibrated at the factory and can be zeroed by the user using the thumb screw on the back. The red arrow which indicates tension is color-coded to match the Newton scale.

Even if the mounting rod is not plumb, the Tension Protractor’s degree scale can be adjusted to read 90 degrees vertically by rotating the outer ring until the string with a hanging mass aligns with 90 degrees.


  • One Tension Protractor

Two Tension Protractors show the tension in the left string is greater than in the right string because the angles are different.

Tension Protractor provides easy reading of angle of string and tension reading (red arrow).


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