Force applied to a body can set it in motion, but also this effort is capable to lead to rotation of a body around the set axis. Thus, force can make both rotary, and progress.
Theoretical bases
Moment of force, or as it is called still, torque, is defined as the work of size of force and value of perpendicular distance from a point of application to a rotation axis.
If influence of the moment is capable to turn the case of a body clockwise then enclosed in that case torque it is considered negative. And vice versa – if the enclosed moment directs the case counterclockwise, then such rotating point is considered good. Torque is the vector size having the direction and measured in newton-meters.
There is a simple example in which force can make rotary motion. When you open a door, you use force (you push or you pull) for the door handle. If to make attempt to open a door, at the same time putting effort in the middle of a door, then in order that use of bigger force is required to make it. And if now to try to push or pull near the hinge, then it is almost impossible to open a door, even at very big effort. This fact shows that besides force size, an important role is played by a point of application of effort to the rotating body. Thus, follows from the example given above that the rotary effect is more, than more perpendicular distance from a point of application to a rotation axis. Besides, the bigger effort will have bigger effect of turn. Thus, important characteristics of torque are factors of size of the applied force and perpendicular distance from a point of application to a rotation axis.
Torque role
Torque owing to force gives rotary action of force of rather motionless axis or point. It calculates by the work of size of perpendicular distance from the line of action of force to an axis of rotation and force. Torque is represented the Greek letter T (ta): T = R x F, where R - distance from a rotation axis to a point of application of force; F – value of the made effort. It is possible to define the T moment as the quantity of rotary motion which then is multiplied by value of angular shift and subsequently determines the volume of the work done as a result of this rotation. In the same way, to unscrew or disconnect a clamp which is put densely with a bolt the wrench having the long handle is required. At the same time length of a shoulder plays a major role in achievement of result, at the same made effort.