What is the formula of physical mechanics?

1, moment theorem: F=ma (resultant force provides acceleration of the object);

2. Kinetic energy theorem: w = 1/2mV 2- 1/2mV 2 (the work done by external force is equal to the change of kinetic energy of an object);

3. momentum theorem: Ft=mV-mv (the impulse of combined external force is equal to the change of momentum of the object).

Four theorems with obvious physical significance are derived from Newton's differential equation of motion, including momentum theorem, moment of momentum theorem, kinetic energy theorem and centroid motion theorem.

Basic contents of dynamics

Particle dynamics, particle system dynamics, rigid body dynamics, D'Alembert principle, etc. The applied disciplines developed on the basis of dynamics include celestial mechanics, vibration theory, motion stability theory, gyro mechanics, external ballistics, variable mass mechanics and developing multi-rigid-body system dynamics (see vibration, motion stability, variable mass motion and multi-rigid-body system).

There are two basic problems in particle dynamics: one is to find the force acting on the particle when the motion of the point is known, and the other is to find the motion of the particle when the force acting on the particle is known. When solving the first problem, we only need to take the second derivative of the motion equation of the particle to get the acceleration of the particle, and then substitute it into Newton's second law to get the force.