A ball is dropped from the top of tower of height ‘x’ meter  takes ‘n’ seconds to reach the ground . what is its height at   n3 seconds

we know, S=Ut+12at2  height of fall=x=12gn2  ---(1)     after substituting t=nAt a time  t=n3The distance travelled by the bodyS=12gn32 ⇒S=12gn29---(2) substitute eqn(1) in (2) ⇒S=x9 The height of ball from ground is h=x−s h=x−x9=8x9