Quick question on universal gravitation - I think I'm right - need clarifica

AI Thread Summary
Doubling the mass of an object while also doubling its distance from the center of the Earth results in its weight being halved. The calculation using the formula F=Gm1m2/d^2 confirms this outcome, showing that the new force is 1/2 of the original weight. The discussion concludes with confirmation that the solution is correct, and the user expresses gratitude for the assistance. The thread ends with a request to lock the discussion since the question has been resolved.
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[SOLVED] Quick question on universal gravitation - I think I'm right - need clarifica

Homework Statement



What would happen to the weight of an object if its mass was doubled while its distance from the center of the Earth was also doubled?
a) The weight would double.
b) The weight would be quadrupled.
c) The weight would be cut in half.
d) The weight would be unchanged.

Homework Equations


F=Gm1m2/d^2


The Attempt at a Solution



F_new=2(Gm1m2)/(2^2)r^2
F_new=2/4=1/2

Therefore, the weight would be halved. (C)

Am I right in how I figured this out? I only have one chance to get this problem right, so I wanted to make sure the way I'm doing this is correct.
 
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That's exactly right.
 
Looks good to me!
 
Thanks, I got the problem right...if someone could lock this that would be nice.
 
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