Question

12:3 Step 1 Expression for work done by the frictional force on an object is, Here, is coefficient of kinetic friction, mis mass of object, g is gravitational acceleration, and is displacement. Work done is path dependent parameter. In the given case, the person put the box at starting position. Hence, the displacement of the box is zero. Therefore, the work done by the person on the box is zero. Thus, the correct option is oncept Check 6.1 A person pushes a box of mass m a distance d across a floor. The coefficient or kinetic friction between the box and the floor is Hy. The person then picks up the box, raises it to a height h, carries it back to the starting and puts it back down on the much work has the person done on the box? Pagh b) c) Hmgd+2mgh d) Hmgd-2mgh

Answer 1