Really propensity, u got the answer....I got the same solution for the integrall....I think I screwed up in the algebra but still not getting the answer..please help... ok, mgR^2 [ (1/R) - (1/(R+H)) ]= 1/2 mv^2 or, gR^2[ (1/R) - (1/(R+H)) ]= 1/2 v^2 or, gR^2[ ((R+H)-R)/(R(R+H)) ] = 1/2 v^2 or, gR^2[ H/(R(R+H))= 1/2 v^2 .......... when you cross multiply it get all jumbled up and got me something else but not the required answer, can you please see where does it go now............... Thanks