A lever-arm dynamometer converts a measured perpendicular force at a known radius into torque. This calculator performs that ideal moment and unit conversion only.
Webber Dynamometer Interactive Calculator
Enter perpendicular force and moment arm. Outputs omit bearing friction, tare, angular misalignment, dynamic loading and calibration uncertainty.
Equation Used
- Force is nonnegative and perpendicular to the arm.
- Arm length is the perpendicular moment arm.
- The 100 N scale reference and 5 mm error scenario are declared constants.
- The conversion factor is an ideal unit conversion.
- Friction, tare, alignment, calibration traceability, uncertainty, vibration and structural limits are omitted.
Force and Moment Arm
NASA Glenn defines torque as force times perpendicular distance to the pivot. This calculator applies that ideal relation to entered values.
What This Calculator Represents
Use this static comparison to explore force, arm length and torque. The 100 N and 5 mm reference values are assumptions, not instrument specifications.
Torque Calculation
T_lbf-ft=0.7375621493T_Nm
scale use=F%
arm scenario=100(0.005/L)
Worked Example
At 100 N and 0.61 m, ideal torque is 61.0 N m or about 45.0 lbf ft; declared scale use is 100% and the 5 mm arm-error ratio is about 0.82%.
Assumptions and Limits
- Calculated: ideal moment and unit conversion.
- Illustrated: lever arm and perpendicular force.
- Not calculated: instrument friction, calibration, uncertainty, dynamics or strength.
Frequently Asked Questions
Must force be perpendicular?
Yes for T=FL as used here.
Is 100 N the instrument range?
No; it is a declared reference.
Is 5 mm measured error?
No; it is a scenario.
Is friction included?
No.
Is uncertainty calculated?
No.
Can this calibrate a dynamometer?
No.
References
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