What Is Normal Reaction ?How To Find It?
Normal reaction is the force acting among two contact surfaces. Like, if you push a wall, you will feel an opposite force acting on your hands. That's normal reaction.
You can search it by Newton third law, action and reaction are equal. For instance, if a block of 2 kg is lying on a table, it exerts a force of 20N (Mg) on the table, therefore the normal reaction is also 20N