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#1 2012-02-03 11:07:33

ads98
Scratcher
Registered: 2011-05-03
Posts: 100+

Help With Netwon's Law of Gravitation

Hey Scratchers,

If I remember correctly, this is Newton's Law of Gravitation (I just learned this in math, so correct me if I'm wrong):

F = (6.673)(10^-11)(Mm/D²)

F stands for Gravitational Force

M stands for the mass of the first object (in kilograms)

m stands for the mass of the second object (in kilograms)

D stands for the distance between the two objects (in meters)

(Btw, I do realize mass and weight are different. I just thought the mass may be in tons because some scientists were able to figure out the mass of the earth using this equation, and their answer was 6.6 * 10^21 tons.)

Now, my problem is I'm not sure what the units are for the mass of the first and second object, and the distance between the two objects. I also need to know what unit gravitational force would be measured in. I already have a script ready for this, I just need a bit of clarification:

Thanks for the clarification trinary!

when gf clicked//Ugh..I can't create the "set F variable to" block correctly online...
set [D v] to [0]
set [F v] to [0]
set [M v] to [0]
set [m v] to [0]
ask [what's the mass of the first object (in kilograms)?] and wait
set [M v] to (answer)
ask [what's the mass of the second object (in kilograms)?] and wait
set [m v] to (answer)
ask [what's the distance between the two objects (in meters)?] and wait
set [D v] to (answer)
set [F v] to <<(6.673) * ([10^ v] of [-11]) * <(M) * (m)/(D) * (D)>>> 
say (join [the gravitational force of the two objects is] (F))

Last edited by ads98 (2012-02-03 14:52:02)


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#2 2012-02-03 12:54:03

ads98
Scratcher
Registered: 2011-05-03
Posts: 100+

Re: Help With Netwon's Law of Gravitation

Please, anyone?


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#3 2012-02-03 13:56:21

trinary
Scratcher
Registered: 2012-01-29
Posts: 1000+

Re: Help With Netwon's Law of Gravitation

G = 6.673 x 10^-11 N m^2/kg^2

Fgrav = G . Mkg . mkg
          -------------------
                d^2

In other words, kilograms.


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#4 2012-02-03 14:44:00

ads98
Scratcher
Registered: 2011-05-03
Posts: 100+

Re: Help With Netwon's Law of Gravitation

Okay, thanks! So the 1.) Masses of the two objects are in kilograms, and 2.) The distance between the two objects are in kilometers?


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#5 2012-02-03 14:48:41

trinary
Scratcher
Registered: 2012-01-29
Posts: 1000+

Re: Help With Netwon's Law of Gravitation

d is in metres.


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#6 2012-02-03 14:49:40

ads98
Scratcher
Registered: 2011-05-03
Posts: 100+

Re: Help With Netwon's Law of Gravitation

Oh, okay. ☺


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