A body rotates about a fixed axis with an angular acceleration of `5 rad//s^(2)` The angle rotated by it during the time when its angular velocity increases frm 20 rad/s to 30 rad/s (in radian) is

Explanation

For force on q to be zero, charges q and Q must be of opposite of nature. Net attraction force on q due to charge Q= Repulsion force on q due to q
`sqrt(2) F_(A)=F_(R) rArr sqrt(2) (kQq)/a^(2)=(kq^(2))/((sqrt(2)a)^(2)) rArr q=2sqrt(2) Q` Hence `q=-2sqrt(2) Q`