Question

calculate the final speed of a rocket of mass 1000 kg fired from rest if the speed of the exhaust gas relative to the rocket is 1000m/s

Answer 1

let velocity of exhaust gas = ve
let velocity of rocket = vr
ve-(-vr) = 1000 (relative motion)
ve = vr (both are equal and opposite)
2vr = 1000
vr = 500
speed of rocket is 500m/s