Question

a rocket of mass 1000kg containing a propellant gas of 3000kg is to be launched vertically. If the fuel is consumed at a steady rate of 60kg per seconds, calculate the least velocity of the exhaust gas if the rocket and content will just lift off the launching pad immediately after firing?

Answer 1

F = d momentum/dt = mass/second * v
so
F = 60 kg/s * v
= m g = (1000+3000) (9.81)
so
v = 4000*9.81 / 60

Answer 2

force=thrust=mg
massrate*v=mg
60kg/sec*v=4000kg*9.8N/kg
solve for v

Answer 3

A rocket of mass 1000kg contaning a propellant gas of 3000kg

Answer 4

1000AND3000

Answer 5

Ft=M(V-U). Divide all by T. F=M\T(∆V). Mass one=1000kg Mass two =3000kg. Total mass =1000+3000=4000kg. Acceleration =10m\s^2.Force =M×A=4000×10=40000. Rate=M\T=60kg\s. 40000=60(∆V). Velocity =666•67m\s.

Answer 6

F=d/dt
Mg=d/dt
4000*10=60v
v=666.7