How Can a Space Capsule Stop Rotating After a Collision?

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Homework Help Overview

The discussion revolves around a physics problem involving a space capsule that is rotating after a collision. The objective is to determine how to stop this rotation using jets that eject gas, with specific parameters provided such as the rotation speed, moment of inertia, and characteristics of the jets.

Discussion Character

  • Exploratory, Assumption checking, Mathematical reasoning

Approaches and Questions Raised

  • Participants discuss the relationship between angular momentum and the forces exerted by the jets. Some express uncertainty about how to initiate their calculations, while others attempt to derive relevant equations related to momentum and angular acceleration.

Discussion Status

The discussion includes various attempts to approach the problem, with some participants questioning their starting points and others providing partial insights into the calculations involved. There is no explicit consensus, but several lines of reasoning are being explored.

Contextual Notes

Participants note the constraints of the problem, including the specific parameters given for the jets and the moment of inertia. There is also mention of forum rules regarding the posting of complete solutions, which influences the nature of the responses.

pantherfan11
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1. The figure shows the rear view of a space capsule that was left rotating about its axis at 6 rev/min after a collision with another capsule. You are the flight controller and have just moments to tell the crew how to stop this rotation before they become ill from the rotation and the situation becomes dangerous. You know they have access to two small jets mounted tangentially, at a distance R = 3 m from the axis, as indicated in the figure. These jets can each eject 29 g/s of gas from each jet with a nozzle velocity of 800 m/s. Determine the length of time these jets must run to stop the rotation. In flight, the moment of inertia of the ship around its axis (assumed constant) is known to be 5800 kg·m2.





2. omega = alpha(time)
v = r(omega)
a = r(alpha)

3. I don't know where to start on this, my attempts would not be worth posting
 
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I realize this is a very old thread but I thought this was a good problem and I wanted to practise some LaTeX.

[Moderator Note] Latex and complete solution removed.
 
Last edited by a moderator:
This is indeed a very old thread, but we still do not allow complete solutions to be posted.

Please don't use the forum to practise your latex skills. Latex image generation (and storage) requires a significant proportion of the server's resources. There are several sites on the internet which do allow you to practise latex or alternatively, you could download the software yourself.
 
First of all, u need to find momentum force M caused by nozzle.
We have M=dL/dt ( L stands for linear momentum caused by the deflating gas), also dL=mvRdt . So M=mvR=800*29*10^-3=23.2
Then alpha=M/I=0.012 and so on...
[Moderator Note] Answer removed[/color]
 

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