Question

give the reason why contact forces are easy to understand than non-contact forces.

Answer 1

In an introductory physics course one learns about contact and non contact forces. Non contact forces are forces that act at a distance like gravity, electromagnetism, the weak and strong nuclear forces, and others. Contact forces are ones that require a collision, like a ball bouncing off the floor or a car hitting another car.

Contact and non contact tends to lose meaning after you get deeper into physics though, as it turns out all forces are caused by interactions that dont really follow either of those ideas.