A ball is dropped from a height .If it takes0.200 second to cross the last 6.00 m before hitting the ground ,find the heightÂ from which it was dropped .
Ans) We need to find HUsing second eqn of motion:6=0.2u-5(0.04).............................u is velocity at h=6mu=31m/sConserving energy:mgh=0.5m(31)2.......................................Datum line for P.E is at 6 m from ground. h= H-6=>h=48.05m=>H=54.05m.
we consider a ball it is dipped from a height equal to square of the intiial distance by 2 multiplide with g(9.8),
i.e ans is 1.83 metres.