Physics

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Resultant Force Calculator.

Calculate force-vector magnitude from Cartesian components.

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Set your values

Results update as you type.

Resultant force: 5 N

Resultant force

5.000000N

Results update automatically as you type.

Use Cases

Physics homework and problem solving

Quickly verify the magnitude of a resultant force when given components in three dimensions, saving time on manual calculations.

Example: Given Fx = 3 N, Fy = 4 N, Fz = 0 N, the resultant magnitude is 5 N.

Engineering statics and dynamics

Determine the magnitude of a force vector from its orthogonal components in structural or mechanical analysis.

Example: For Fx = 100 N, Fy = 50 N, Fz = 25 N, the resultant is about 114.5 N.

Frequently Asked Questions

How do I use the Resultant Force Calculator?
Enter the Cartesian components of the force vector: Fx, Fy, and Fz, each in newtons (N). The calculator computes the magnitude of the resultant force using the formula sqrt(Fx^2 + Fy^2 + Fz^2).
What units does the calculator use?
All input fields (Fx, Fy, Fz) are in newtons (N). The result is also in newtons, representing the magnitude of the resultant force vector.
Can I use this calculator for 2D forces?
Yes, if you have only two components, set the third component (e.g., Fz) to 0. The calculator will still compute the correct magnitude for a 2D force vector.

Tips & Common Mistakes

Tips

  • Ensure all components are in newtons (N) before entering them; the calculator assumes consistent units.
  • If a component is zero, you can leave it as 0; the calculator handles it correctly.
  • Double-check the signs of your components: negative values are allowed and will affect the magnitude only through squaring.
  • Use the result as a reference; for precise engineering work, consider significant figures and rounding rules.

Common Mistakes to Avoid

  • Forgetting to square each component before summing; the calculator does this automatically, but manual checks should follow the same rule.
  • Entering components in different units (e.g., pounds instead of newtons) without conversion, leading to incorrect results.
  • Assuming the calculator gives the direction of the force; it only provides the magnitude, not the angles.

Last updated: August 13, 2026