Where did I go wrong? (1 Viewer)

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Calculate how far an astronaut would need to be away above the Earth in order for his weight to be 0.01 his weight on the Earth's surface.


Where did I go wrong?
 

Aquawhite

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What is your second last step involving, and what is the correct answer?
 
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What is your second last step involving, and what is the correct answer?
The question asks "above the Earth" so I subtracted the radius of the Earth.

The correct answer is 1.93x105, however, it's from the Dot Point book which is plagued with incorrect answers.
 

Physics_FTW

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The value you have gotten is correct for the question asked.

Easy way to check would be to sub in your 'r' value in the eqn 'g = GM/r^2'

Your r value comes out to a g of around 0.098 (which is 0.01 of g on earth)

Their r value comes out to a g of around 9.268. WRONG.
 

danjw

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I did the working and got the same answer as you, I also tried a different method and still got the same answer. I think you're right the book must be mistaken.
 

hscishard

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I got the same answer... and everything you did looks right . Need another person to determine if the book is wrong again
 

hscishard

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The value you have gotten is correct for the question asked.

Easy way to check would be to sub in your 'r' value in the eqn 'g = GM/r^2'

Your r value comes out to a g of around 0.098 (which is 0.01 of g on earth)

Their r value comes out to a g of around 9.268. WRONG.
I did the working and got the same answer as you, I also tried a different method and still got the same answer. I think you're right the book must be mistaken.
I got the same answer... and everything you did looks right . Need another person to determine if the book is wrong again
Yea
 

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