25.A body falls freely from the top of tower. It covers 36 % of total height in the last second, before striking the ground level, the height of the tower is
solution: a body falls freely from the tower ,it means it has initial velocity is zero. we have formula ,The total time taken is ‘t’ S= ut +(1/2)at2 Total height (H)=(1/2)g(t)2 …………. (1) For remaining 64% covered in (t-1) seconds (64/100)H=1/2g(t-1)2 ……………….(2) Equation (1)/Equation(2) 1/(64/100)=(t)2 /(t-1)2 (t/t-1)=10/8 t=5sec then, Total height (H)=(1/2)g(t)2 =(1/2)*10*5*5 H =125m