A rectangle block rests on a horizontal table. A horizontal force is applied on the block at a height h above the table to move the block. Does the line of action of the normal force N exerted by the table on block depend on h?

Explanation

Normal force is a contact force. If two surfaces are not is contact they cannot enert a normal force on each other. Friction is always perpendicular to the normal force N acting between the surfaces. It acts tangential to the surface of contact.
A normal force `f_(n)` is the force on a body from a surface against which the body presses. The normal force is always perpendicular to the surface.