Answer:
According to the newton's second law,
[tex]F = ma[/tex]
let's apply it to this case. Force has a direct relation with mass and acceleration which means if mas decrease then there will be a decrease in force too. But as it is mentioned that the engine is producing the constant thrust force so there must be an increase in acceleration to balance that. So with time the rocket will accelerate or there will be an increase in it's acceleration.
Explanation:
