Rocket Propulsion Gas Injection

AI Thread Summary
To achieve an initial acceleration of 25.0 m/s², the rocket must eject a specific amount of gas in the first second. Given the rocket's initial mass of 6000 kg and a gas ejection velocity of 2000 m/s, the conservation of momentum principle is applicable. Calculating the required mass of gas involves applying the rocket equation and considering the forces involved. The discussion emphasizes the need for practical examples to clarify the calculations. Understanding these principles is crucial for solving rocket propulsion problems effectively.
ada0289
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Please help, book gives no examples relatively close to this.

A rocket is fired in deep space, where gravity is negligible.


If the rocket has an initial mass of 6000 kg and ejects gas at a relative velocity of magnitude 2000 m/s , how much gas must it eject in the first second to have an initial acceleration of 25.0 m/s^2?
 
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Welcome to PF!

Hi ada0289! Welcome to PF! :smile:
ada0289 said:
If the rocket has an initial mass of 6000 kg and ejects gas at a relative velocity of magnitude 2000 m/s , how much gas must it eject in the first second to have an initial acceleration of 25.0 m/s^2?

Hint: use conservation of momentum :wink:

What do you get? :smile:
 

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