Conservation of Momentum Spaceship Question

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Homework Help Overview

The problem involves the conservation of momentum in a scenario where a spaceship at rest ejects a part of its mass. The original poster presents the mass of the spaceship and the speed of the ejected part, seeking to determine the speed of the remaining part.

Discussion Character

  • Exploratory, Assumption checking

Approaches and Questions Raised

  • Participants discuss the application of conservation of momentum, with some attempting to set up equations based on initial and final momenta. Questions arise regarding the mass of the remaining part of the spaceship and the calculations involved.

Discussion Status

There is an ongoing exploration of the problem, with participants providing corrections and alternative calculations. Some guidance has been offered regarding the setup of the momentum equations, and participants are actively questioning the assumptions made about the masses involved.

Contextual Notes

Participants are addressing potential errors in the original post's assumptions about the mass of the remaining part of the spaceship, which affects the calculations. There is a focus on ensuring the correct application of the conservation of momentum principle.

qwertyqwert321
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Homework Statement


The mass of a spaceship is 10012 kg. The spaceship is at rest. Then one part of the ship with a mass of 1000 kg is ejected and emerges with a speed of 112 m/s. What is the speed of the other part?

Homework Equations

The Attempt at a Solution


I tried:
pi=pf
mivi=mfv2
10012 (vi)= 1000 kg * 112 m/s
solved for vi and got 11.19 m/s.
Am I correct? or did i need to assume the other part of the spaceship is 12 kg?[/B]
 
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You have to apply conservation of momentum here, where pf is the sum of the momenta of the two pieces of the ship.
 
so would it be :
pi=pf
mivi = m1v1 + m2v2
(10012 kg)(0 m/s) =m1v1 + m2v2
0= (1000 kg)(112 m/s)+ (12 kg) (v2)
v2 = -9333.3 m/s
 
Last edited:
That's more like it! Include some directions and you are golden. :)
 
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Is the original post accurate? What do you get when you subtract one thousand from ten thousand?
 
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Good point.
 
jbriggs444 said:
What do you get when you subtract one thousand from ten thousand?
oh man... i totally messed up there, thank you so much for the correction! m2 will then = 9012
(10012 kg)(0 m/s) =m1v1 + m2v2
0= (1000 kg)(112 m/s)+ (9012 kg) (v2)
v2 = -12.43 m/s
 
Last edited:

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