Question

a man standing near the top of an old wooden step ladder feel unstable?

Answer 1

he is feeling unstable because as the ladder is very high his center of gravity will be at very high ,we can assume that stability of a object is inversely proportional to center of gravity means as the height of the object keep on increasing the stability will be keep on decreasing.(this only happens when the width of base is less)

Answer 2

Answer:

The ladder can rotate about the point of contact of the ladder with the ground. When the labourer is at the top of the ladder, the lever arm of the force large. Hence the turning effect on the ladder will be large.

hope this helps you..