A mother is helping her children, of unequal weight, to balance on a seesaw so that they will be able to make it tilt back and forth without the heavier child simply sinking to the ground. Given that her heavier child of weight WWW is sitting a distance LLL to the left of the pivot, at what distance L1L1L_1 must she place her second child of weight www on the right side of the pivot to balance the seesaw

W x L / w

Explanation:

Weight of heavier child = W

Weight of second child = w

distance of heavier child from the pivot = L

distance of second child from the pivot is L1.

By using the principle of moments, in the equilibrium condition

Anticlockwise moment = clockwise moment

According to the diagram

The distance of the second child from the pivot is W x L / w.

weight of the box is given as

here this is placed on the inclined of angle 42 degree

now this weight will have two components one is along the incline other is perpendicular to it

so here we need to apply a force parallel to incline opposite to its component of weight

so here the component of weight is given as

here we have

so it requires 75 n force to move it upwards