Question 88420

 The distance an object falls is directly proportional to the square of the time it has been falling.  After 6 seconds it has fallen 1296 feet.  How long will it take to fall 2304 feet?

  Let the distance be = d
  time taken          = t 
  The relation given in th sum is , d proportional to (t)^2
                       i.e, d = k.t^2  to find the value of k substitute the 
 values of t= 6 sec  and d = 1296

                  d = k.t^2
              1296  = k.(6)^2
                  k = 1296/6.6 = 1296/36 = 36
 to find the value of t  substitute the values of k and d in the eq'n d = k.t^2
                   2304 = 36.(t)^2  
                    2304/36 = t^2
                      64 = t^2
                       t = sqrt of 64 = 8
   it will take 8 seconds to fall 2304 ft.