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Trying to figure out gravitational attraction between two objects.

  • Thread starter LuigiHomer
  • Start date
Trying to figure out the gravitational attraction between two objects using Newton's Law of Universal Gravity.Need to figure out what the force is.Here is a model.If anything is in ordinary parentheses then it is an exponent.

----------------------G
--------____________|_____________400x300
F1=F2=[6.673x10(-11)N m(2) kg (-2)] -----
-------------------------------------2,000(2)






Force is proportional to the product of the two masses{120,000}and inversely proportional to square of distance between two point masses.{4,000,000}




Please help me figure out what F1 is,since F1 is equal to F2.

-LH
 

DaveC426913

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First thing you must do is ensure all your numbers are in the right units: kilograms & metres (since those are the units that G is in). I don't know what units your numnber are in now.

F - the force between them - will be equal to your formula there.
 
Okay.The two point masses are in KG.The distance is in metres.G is in Newtons.
 

DaveC426913

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So, what answer did you get?

The formula you have listed will calculate "the force of attraction between two bodies". One force, not two. Not sure where the F1=F2= came from.
 
I can't figure it out.Kind of new to the concept of using Newton's laws.Kind of new to physics.
 
I would think F1 is force felt by object #1 and F2 is the force felt by object #2, and they are equal in magnitude, while opposite in direction.

Simply multiply and divide and you are done.

G x M1 X M2 / (R x R) = F1 = F2

From your post we have:

M1 = 400 KG
M2 = 300 KG
R = 2000 M

And we know G.

So, just do the math! There's no physics left to figure out.
 
I don't have a calculator that can even REGISTER newtons,and our teacher took it away.:(What a meanie.
 
My sister THINKS it is 0.030.
 
Do you guys have a suggestion
for a good, reliable computer calculator for free that can do what Molinaro said to do?
 
@ DaveC,It is that they BOTH exert gravitational force.F1 is equal to F2,which is the other force.
 
Do you guys have a suggestion
for a good, reliable computer calculator for free that can do what Molinaro said to do?
> START > PROGRAMS > ACCESSORIES > CALCULATOR

then menu > VIEW > SCIENTIFIC
 
My sister didn't incorporate G.My head hurts.I'm only in 5th grade,you know.
 
I think it's 0.6.Please help me.More.
 

DaveC426913

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I don't have a calculator that can even REGISTER newtons,and our teacher took it away.:(What a meanie.
You don't need a calculator that registers' Newtons...
You're just doing math.
 

DaveC426913

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@ DaveC,It is that they BOTH exert gravitational force.F1 is equal to F2,which is the other force.
They do both exert a force. That formula will calculate the entire forfce between the two masses.
 

DaveC426913

Gold Member
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1,728
Once again,I AM A FIFTH GRADER!
I'm sorry, I missed that.

Have you learned exponents?
6.67x10^-11 is equal to .0000000000667

So:

F = (.0000000000667)*400*300 / (2000^2)

Masses of 300-400kg that a distance of 2km have an extremely small force of attraction.
Your answer should be a very, very small number - about 11 zeros.
 

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