Engineering Mechanics

  Principle of transmissibility: If a force is acting at a point on a body then it is assumed that the point of application of a force can be transmitted anywhere on its line of action within the body (without disturbing its condition of equilibrium).  Following figure shows the force F is acting at a point 'A' on the body and the new position is represented at point 'B' on the same line of action, within the body.

Definition of friction: I two bodies are in contact with each other and one of them is allowed to move over the other, then the resistance to motion produced. This resistance to motion is called as friction. The friction is also called as force of friction, frictional force, frictional resistance etc. The friction is due to the roughness of the surface. Friction is depends on the nature of surface. And is independent of area in contact. For the smooth surface the friction is zero. Types of friction: There are two types of friction, 1) Static friction 2) Dynamic friction 1) Static friction: If a body is kept on a ground (or on the surface of other body) and is in equilibrium, then the friction experienced by a body is called as static friction. 2) Dynamic friction: If a body is moving on the surface of ground (or on the surface of other body), then the friction experienced by a body is called as dynamic friction. There are two types of dynamic friction: i) Sliding fric...