Mechanics – Statics
Tension Protractor ME-6855 A Measure Tension and Angle with one device A Large scale for viewing demonstrations A Zero-adjust for torsion spring scale
The tension in the left string is greater than in the right string because the angles are different.
A Built-in rod clamp 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.
String
Zeroing Ring for Angle Scale
Rod Clamp
30° angle reading
Arrow indicates tension reading (5.0 N)
mounts on either a vertical or horizontal rod.
Zeroing Thumb Screw for Force Scale
Specifications Force Range: 0 N to 10 N Smallest Force Division: 0.1 N Force Accuracy: ±4% of Reading Angle Range: -90° to +90° Smallest Angle Division: 1° Diameter: 15 cm
Includes: One Tension Protractor
Order Information: Tension Protractor. .......................................................................................ME-6855 Recommended: Large Table Clamp.........................................................................................ME-9472 p.215 90 cm Long Rod...............................................................................................ME-8738 p.212 Multi-clamp. ..........................................................................................................SE-9442 p.214 Hooked Mass Set...........................................................................................SE-8759 p.223
A 50 gram mass hangs vertically from the Tension Protractor: The tension reads 0.5 N as expected and the outer degree scale is dialed to align the 90° mark with the string. This compensates for unlevel tables or bent rods.
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