پروز ِ دالامبر parvaz-e d'Alembert
*Fr.: principe de d'Alembert*
The statement that a moving body can be brought to a
→ *static equilibrium* by applying an imaginary inertia force
of the same magnitude as that of the accelerating force but in the opposite direction.
More specifically, when a body of mass *m* is moving with a uniform acceleration
*a* under the action of an external force *F*, we can write:
*F = m . a*, according to Newton's second law. This equation can also be
written as: *F - ma = 0*. Therefore, by applying the
force *-ma*, the body will be considered in equilibrium as the sum of
all forces acting on it is zero. Such equilibrium is called
→ *dynamic equilibrium*.
Owing to this principle, dynamical problems can be treated as if they were statical. Named after the French mathematician and philosopher Jean le Rond d'Alembert (1717-1783), who
introduced the principle in his
*Traité de dynamique* (1743). |