Question

Which of the forces involved in
dragging a heavy object on a
smooth, horizontal surface, have
the same magnitude?
I) The horizontal applied force
II) gravitational force
III) reaction force in vertical direction
IV) force of friction ​

Answer 1

On a smooth horizontal surface the friction is like minimum.

I think the force of friction has to be involved in dragging a heavy object on a smooth horizontal surface have the same magnitude. A force of friction is any force that opposes the motion of an object due to the contact of the object with other bodies.