Statement-1: One end of a string of length R is tied to stone of mass m and the other end to a small pivot on a frictionless vertical board.The stone is whirled in a vertical circle with the pivot as the centre.The minimum speed the stone must have,when it is at the topmost on the circle,so that the string does not slack is $\sqrt{gR}$
Statement-2: At the topmost point on the circle,the centripetal force is provided partly by tension in the string and partly by the weight of the stone
$\begin{array}{1 1}\text{Statement-1 is true,Statement-2 is true and Statement-2 is the correct explanation for statement-1}\\\text{Statement-1 is true,Statement-2 is true but Statement-2 is NOT the correct explanation for Statement-1}\\\text{Statement-1 is true,Statement-2 is false}\\\text{Statement-1 is false,Statement-2 is true}\end{array} $