Force Diagram Builder

Interactive simulation — adjust parameters and watch the visualization update in real time.

How it works

Add up to four forces on a single object. Each force has a magnitude (newtons) and an angle measured from the +x axis counterclockwise — 0° points right, 90° points up. Colored arrows are the forces you enable; the thick cyan arrow is the net force ΣF. The dashed magenta arrow is acceleration a = ΣF/m (same direction as ΣF; length is scaled for visibility). The diagram redraws every frame as you move the sliders.

Key equations

F_x = |F| cos θ,   F_y = |F| sin θ
ΣF = Σ F_i   (vector sum)
a = ΣF / m