Question

Three small balls each of mass 100gram are attached

Answer 1

Answer:

F= Electrostastic force between two charged balls.

`sqrt3F=`Resultant of electrostatic force on any one balll from rest two balls.

`a=lcos60^@=10cm`

`r=2acos30^@`

`(2)(10)(sqrt3/2)=10sqrt3cm`

Now applying Lami's theorem for the equilibrium of ball we have

`(mg)/(sin(90^@+30^@))=(sqrt3F)/(sin(90^@+60^@))`

`F=(mg)/3=1/(4piepsilon_0)((q)(q))/r^2=(mg)/3`

`:. q=sqrt((mgr^2)/(3(1//4piepsilon_0))`

`=sqrt(((0.1xx10^-3)(9.8)(10sqrt3xx10^-2)^2)/(3xx9xx10^9))`

`=3.3xx10^-8C`

hope it helps u