A nail is located below the point of suspension of a simple pendulum of length l. The bob is released from horizontal position. If the bob loops a verticle circle with nail as centre, find the distance of nail from point of suspension.

A nail is located below the point of suspension of a simple pendulum o

1.	A nail is located below the point of suspension of a simple pendulum of length l. The bob is released from horizontal position. If the bob loops a verticle circle with nail as centre, find the distance of nail from point of suspension.
Answer» Solution :Form the principle of conservation of mechanical energy PE at the horizontal position = KE at the LOWEST position. `mgl = (1)/(2) mv^(2)` To loop the vertical circle , `V^(2)=5g(1-X)` where .x. is the distance of nail from point of SUSPENSION, and .v. is the velocity at lowest point of path. `(mgl=(1)/(2)m.5g (l-x)), l=(5)/(2)(l-x), "" x = 3l//5`