Action and reaction of a rocket in space.

[Clara Chung]

By conversation of momentum, the rocket can be propelled forward by ejecting mass like gas.
However, how is the propelling force explained in terms of action and reaction? If gas is ejected, what does the force act on?

 

[russ_watters]

If gas is ejected, what does the force act on?

The rocket.

 

[A.T.]

By conversation of momentum, the rocket can be propelled forward by ejecting mass like gas. However, how is the propelling force explained in terms of action and reaction?

Conversation of momentum is ensured by Newton's 3rd Law (action and reaction).

 

[Drakkith]

If gas is ejected, what does the force act on?

Russ already answered this, but think for a moment. What's acting on the gas to eject it? Where's that force coming from? If the combustion process inside the engine creates a high speed gas, what forces it to go one way instead of expanding outwards in all directions?