The rate of burning of fuel in a rocket is 50 g/sec and comes out with a velocity 4X1000 sec. then find the force extended by fuel on the rocket.

Answer 1

4000 meters / second maybe?

Newton #2:
Force = change in momentum / time
(F= m a if m is constant but here it is not)

change in momentum/second = [.050 kg * (4000 - 0) m/s]/second

= 200 Newtons