Posted by Tumur on .
A rocket if fired vertically up from ground with resultant vertical acceleration of 5m/s.The fuel is finished after 2 minutes and the rocket continues to for sometime.How long after fire the max height will be reached?

physics 
shraddha roy,
the distance traveled by the rocket in 2 minutes (120 s)a =5 m/s.s upward is
h1=1/2* 5*120*120=36000m=36km
velocity=5*120=600m/s
after 2 minutes the rocket moved upward with the velocity 600m/s and downward acceleration due to gravity till its velocity becomes zero.
0=(600*600)2gh2
=(600*600)2*10*h2
h2=18000m=18m
total distance=(36+18)=54km