Welcome to our website!...

The Second law of Newton

In the formulation of the second law Newton has entered concepts:

· Acceleration - vector size (Newton named its quantity of movement and considered at a formulation of a rule of a parallelogram of speeds), defining speed of change of speed of movement of a body.

· Force - the vector size understood as a measure of mechanical influence on a body from other bodies or fields as a result of which influence a body gets acceleration or changes the form and the sizes.

· Weight of a body - physical size - one of the basic characteristics of the matter, defining its inertial and gravitational properties.

The second law of mechanics says: the force acting on a body, is equal to product of weight of a body on acceleration informed by thus force. Its modern formulation is those. Newton has formulated it differently: change of quantity of movement to proportionally enclosed operating force also occurs in a direction of that straight line on which this force operates, and in inverse proportion to weight of a body or mathematically:

On experience it is easy to confirm this law, if to the end of a spring to attach the carriage and to release a spring in time t the carriage will pass a way s1 (fig. 1), then to attach to the same spring two carriages, i.e. to increase weight of a body twice, and to release a spring for same time t they will pass a way s2, twice smaller, than s1.

This law also is fair only in inertial systems of readout. The first law from the mathematical point of view represents a special case of the second law, because if equally effective forces are equal to zero also acceleration also is equal to zero. However the first law of Newton is considered as the independent law since it approves about existence of inertial systems.