A boy and a man carry a uniform pole of length 8m and of mass 60kg by supporting it on their shoulders. They are located at the ends of the pole. Where should a load of 90kg be suspended from boy's end so that boy carries only one-third of the total load ?

A boy and a man carry a uniform pole of length 8m and of mass 60kg by

1.	A boy and a man carry a uniform pole of length 8m and of mass 60kg by supporting it on their shoulders. They are located at the ends of the pole. Where should a load of 90kg be suspended from boy's end so that boy carries only one-third of the total load ?
Answer» Solution :The mass of pole ACTS from its CENTRE .C.. LET the load be placed at a distance .x. from the boy.s end. If `N_(1)`, `N_(2)` are the normal reactions on man and boy respectively then `N_(1)=(2)/(3)(60+90)g=100gN` `N_(2)=(1)/(3)(60+90)g=50gN` Taking TURNING effects about boy.s end .B., we have. `N_(1)xx8-60gxx4-90gxx x=0` or `100gxx8-60gxx4-90g XX x=0` on solving `x=6.22m`