recently i came across quesiton:(adsbygoogle = window.adsbygoogle || []).push({});

a rocket car movves on str horz track. half of car mass is propellent, during run, propellent consumed at constant rate and ejected at constant nozzle velocity

the answer says that force is constant but accel is increasing

however i got a major question:

by defitiion thrust of rocket is -dm/m=dv/u where u is the exit speed so rearranging

-udm/dt=mdv/dt,

but thrust of rocket is -udm/dt, let this be T(constant)

however F=dp/dt=mdv/dt+vdm/dt=T+vdm/dt

however v is changing for rocket due to acceleration and dm/dt is constant and T is constant, does that not mean F is not constant on rocket car ????

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# Homework Help: On rocket thrust

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