An example of contact force commonly encountered in college-level physics is the force between two masses A and B which are lying next to each other and a force F is being applied on one of the masses, for example A. In such a case, the contact force will be proportional to the mass of B.Hence, we can see the many examples of contact forces in everyday life. Contact forces can act through a rigid connector or a non rigid connector .For example when a boy pulls a cart through a rope he is connecting the force applied through a non rigid connector(the rope) He could also pull the cart through the handle of the cart hence transferring the force through the rigid connector (the handle)But from case A the boy cannot push the cart(disadvantage of non rigid connector )From this investigation we can prove that: a rigid connector can push or pull but a non rigid connector can only pull .