How Do You Calculate the Change in Gravity as a Rocket Travels Away from Earth?

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To calculate the change in acceleration due to gravity as a rocket travels away from Earth, one can use the universal law of gravitation, expressed as F=(G*m1*m2)/(R^2). The discussion emphasizes the importance of understanding the forces acting on the rocket and its changing mass over time. It also suggests two methods: applying Newton's law for radial decline or analyzing the rocket's motion as a centripetal force in a circular orbit. Participants are reminded to post homework-related questions in the appropriate forums. Understanding these concepts is crucial for accurately determining gravitational changes during a rocket's ascent.
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If a rocket launches from the earth, how can i calculate the change in acceleration due to gravity as it gets farther and farther away? Thanks!
 
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Well, if you're familiar with the universal law of gravitation.. F=(G*m1*m2)/(R^2). And F=ma so...
 
This looks like a homework problem. Had you submitted this in our homework section, you would have been prompted to tell us the relevant equations and describe the work you have done to solve the problem. So, lacking those automated prompts, I am prompting you now. What are the relevant equations and what have you done to solve the problem?
 
it actually is not a homework problem...
In response to Nabeshin-
Ok I thought i could just do this but someone told me otherwise...
 
rhines8 said:
it actually is not a homework problem...
In response to Nabeshin-
Ok I thought i could just do this but someone told me otherwise...

Thread moved to Homework Help anyway. Please take care to post anything homework-like in the Homework Help forums. The PF Rules (see link at top of the page) are pretty clear about that.

And on your question -- what can you tell us about the sum of the forces on the rocket, and how that sum is related to the rocket's acceleration? Also, what can you tell us about the rocket's mass over time...?
 
rhines8 said:
If a rocket launches from the earth, how can i calculate the change in acceleration due to gravity as it gets farther and farther away? Thanks!

Depends, either let it decline radially through Newton's law, or you could use a rotating rocket around the earth, and try and calculate its minimum height with corresponding speed to rotate around earth, using gravitational acceleration as a centripetal force.
 
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