Net Force Calculator

How it works

1. 1Choose “Along a line” to enter up to three colinear forces (positive = one direction, negative = the opposite), or “Perpendicular (x, y)”.
2. 2Each force is converted to newtons, then summed: along a line the signed values add; perpendicular gives √(Fx² + Fy²) and the angle.
3. 3The result is converted back to your unit system. A positive 1-D result acts in the positive direction; zero means equilibrium.

Use cases

• Physics students checking whether forces on a block produce a net acceleration or equilibrium.
• Engineers resolving cable and structural loads into a resultant force before sizing members.
• Teachers building worked examples of Newton’s second law for colinear and perpendicular forces.

Frequently asked questions

What is net force and how is it calculated?

Net force (ΣF) is the vector sum of all forces on an object. Along one line you add signed values: 10 N right + (−4 N) = 6 N right. For two perpendicular components the magnitude is √(Fx² + Fy²) and the direction is arctan(Fy ÷ Fx). Then a = ΣF ÷ m.

What does it mean when net force equals zero?

ΣF = 0 is the condition for translational equilibrium: the object is stationary or moves at constant velocity (zero acceleration). Example: a 20 N push balanced by 20 N of friction gives ΣF = 0.

Can you show a worked example for each mode?

Along a line: 10 N, −4 N, 0 N → net = 6 N in the positive direction. Perpendicular: Fx = 3 N, Fy = 4 N → magnitude = √(3² + 4²) = 5 N at arctan(4 ÷ 3) ≈ 53.1° from the +x axis.