• # question_answer 1) An iron block of sides $5cm\times 8cm\times 25cm$ has to be pushed along the floor. The force required will be minimum when the surface in contact with ground is: A) force is the same for all surfacesB)  $8\,cm\times 5\,cm$ surfaceC)  $5\,cm\times 15\,cm$ surfaceD)  $8\,cm\times 15\,cm$ surface

Sides of block $=5cm\times 8cm\times 15cm.$. The force required to push the iron block is independent of the area of contact. Therefore required forces will be same for all the surfaces.