Rocket's acceleration in terms of law of conservation of momentum (1 Viewer)

[ProcrastinATAR]

I always had troubles understanding this concept.

the dotpoint says.

Analyse the changing acceleration of a rocket during launch in terms of the
Law of Conservation of Momentum and the forces experienced by astronauts

Can someone please explain what I need to know?

I can understand it with F=MA.
(as fuel decreases, mass decreases but if thrust is constant, acceleration must to increase balance the equation)

I can't explain it using conservation of momentum.

 

[InteGrand]

I always had troubles understanding this concept.

the dotpoint says.

Analyse the changing acceleration of a rocket during launch in terms of the
Law of Conservation of Momentum and the forces experienced by astronauts

Can someone please explain what I need to know?

I can understand it with F=MA.
(as fuel decreases, mass decreases but if thrust is constant, acceleration must to increase balance the equation)

I can't explain it using conservation of momentum.

https://en.wikipedia.org/wiki/Tsiolkovsky_rocket_equation

(See Derivation section, it is derived using conservation of momentum.)

 

[sy37]

Essentially it just wants you to know that the /\P(gases) = /\P(rocket) and thus /\mv(gases) = /\mv(rocket)

This means the backward momentum of the gases equals the forward momentum of the rocket, which is how the rocket acquires forward velocity. The momentum of the exhaust gases stays fairly constant during lift off and beyond since they are being ejected at a calculated rate throughout the flight. To obey the conservation of momentum, the rocket's velocity, v keeps increasing throughout the flight (since mass of rocket decreases as fuel is burnt).