A Stone is dropped from the top of the tower and travel 24.5 m in last second of its journey. the height of the tower is ...?
Distance travelled at nth sec=u + a/2(2t-1)
so here 24.5=0+4.9(2t-1)
hence t=3 secs
it takes 3 secs to reach the bottom so height=1/2gt^2