A wooden box of mass rests on a horizontal concrete floor
PHYSICS · Multi-part · CBSE · Physics · Laws of Motion · Laws of Motion
Problem
A wooden box of mass 20kg rests on a horizontal concrete floor. The coefficients of friction between the wood and concrete are μs=0.40 and μk=0.30. Take g=9.8ms−2.
(i) Calculate the minimum horizontal force required to just set the box in motion.
(ii) If the same horizontal force continues to act after motion begins, determine the acceleration of the box.
(iii) The box is now turned over so that the apparent area of contact with the floor doubles, but its mass and the nature of the surfaces remain unchanged. State with reasons whether your answers to parts (i) and (ii) will change.