You may have seen in a circus a motorcyclist driving in vertical loops inside a ‘deathwell’ (a hollow spherical chamber with holes, so the spectators can watch from outside). Explain clearly why the motorcyclist does not drop down when he is at the uppermost point with no support from below. What is the minimum speed required at the uppermost position to perform a vertical loop if the radius of the chamber is 25 m

Explanation

When motorcyclist is at the heighest point of the motorcyclist by the celling of the chamber .His weight also will be in downward direction centripetal force acting on him .
`:. ,R + mg (mv^(2))/( r )`
`m=`mass of motorcyclist
Because of balancing of force the motorcylist will not drop
Minimum speed required to perform in vertical loop `v_(min)`
`mg = (mv^(2))/( r )`
`= sqrt(245)`
`= 15.05ms^(-1)`