Lami's theorem

In statics, Lami's theorem is an equation relating the magnitudes of three coplanar, concurrent and non-collinear forces, which keeps an object in static equilibrium, with the angles directly opposite to the corresponding forces. According to the theorem,

A sin ⁡ α = B sin ⁡ β = C sin ⁡ γ

where A, B and C are the numerical values of three coplanar, concurrent and non-collinear forces, which keep the object in static equilibrium, andl α, β and γ are the angles directly opposite to the forces A, B and C respectively.

Lami's's theorem is applied in static analysis of mechanical and structural systems. The theorem is named after Bernard Lamy.