Question

If you are trying to push a heavy box on a horizontal surface, list various forces on the box. State the condition under which this box will start sliding on the surface. How will the magnitude of applied force required to move the box change if:



(i) weight of the box is increased,



(ii) the surface on which the box is placed is made more rough ?



answer:

Answer 1

in 1 st case

increase in W of box is independent of the horizontal motion

becoz W is cancelled by normal reaction

which is acting perpendicular to the

surface

in 2 nd case...

Friction= coefficient of friction*mg

as the surface is rough

so..coeff increase

so..diff to move

more force rqed