Current through a wire decreases from 4 A to zero in 10sec. Calculate charge flown through the wire during this interval of time.

Explanation

The `y-`axis is the line of symmetry, therefore mass center of the ring lies on it making x-cordinate zero. Distance OC of mass center from center is given by the result obtained in example 4. Making use of this result, we have
`OC = (r sin theta)/(theta)rarr y_(c ) = (r sin (pi //2))/(pi//2) = (2pi)/(pi)`