<PRE><B>Question 216616</B>
The  vertical  drop  is  only  related  to  the  height  and  gravity by,
.
d= 1/2 gt^2,,,,where  d=distance (m),,,g=9.81 (m / sec^2),,,  and  t=time (sec)
.
500 m = 1/2 *9.81 *t^2
.
500*2/9.81 = 101.936 sec^2 = t^2
.
10.0964 sec = t,,,,
.
.
the  velocity  of  the  plane  in  that  time  is  distance  / time
.
v=d/t = 400/10.0964 = 39.618  m/sec
.
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