Thrust is a reaction force described quantitatively by Newton's third law. When a system expels or accelerates mass in one direction, the accelerated mass will cause a force of equal magnitude but opposite direction on that system. Mathematically can be written as,
[tex]T = v\frac{dm}{dt}[/tex]
Here,
v = speed of the exhaust gases measured relative to the rocket.
[tex]\frac{dm}{dt}[/tex]= Rate of change of mass with respect to time
Our values are given as,
[tex]v = 1500m/s[/tex]
[tex]\frac{dm}{dt} = 100kg/s[/tex]
Replacing we have that
[tex]T = 1500*100[/tex]
[tex]\therefore T = 1.5*10^5N[/tex]