Work Power And Energy

A body of \(m \mathrm{~kg}\) slides from rest along the curve of vertical circle from point \(A\) to \(B\) in friction less path. The velocity of the body at \(B\) is:

(given, \(R=14 \mathrm{~m}, g=10 \mathrm{~m} / \mathrm{s}^2\) and \(\sqrt{2}=1.4\))