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Old Jul 8th 2017, 11:59 PM   #1
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Join Date: Jul 2017
Posts: 24
action-reaction

Hello, buddies!

I read a piece of text, where I found a puzzling interpretation of Newton's third law (F1=-F2).

The author gives the following representation: F=Rv(m1m2/l^2)

R - reaction;
m1, m2 - masses;
v - velocity of reaction;
l - distance between the two objects.

Please, help me with explanations about the equation, suggestons about its derivation? I will be grateful for every comment.

The formula reminds me of Newton's law of universal gravitation: F=k(m1m2/l^2)

F - force between the masses;
k - gravitational constant;
m1, m2 - masses;
l - distance between the centers of the masses.

But what is the reason for replacing k (gravitational constant) with Rv .... any ideas?

It is puzzling matter, this author keeps me thrown in confusion...
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Old Jul 9th 2017, 05:00 PM   #2
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Join Date: Aug 2010
Posts: 173
Originally Posted by DesertFox View Post
Hello, buddies!

I read a piece of text, where I found a puzzling interpretation of Newton's third law (F1=-F2).

The author gives the following representation: F=Rv(m1m2/l^2)

R - reaction;
m1, m2 - masses;
v - velocity of reaction;
l - distance between the two objects.
I would like to have more information about this because it makes no sense! In particular, what does "R- reaction" mean? What units does "reaction" have? Is F a force? If so then it has units mass times distance over time^2. Since v(m1m2)/l^2 has units of mass^2 over (time times distance), R would have to have units of distance^2 over (time times mass). I don't know any quantity that has those distances!

Please, help me with explanations about the equation, suggestons about its derivation? I will be grateful for every comment.

The formula reminds me of Newton's law of universal gravitation: F=k(m1m2/l^2)

F - force between the masses;
k - gravitational constant;
m1, m2 - masses;
l - distance between the centers of the masses.

But what is the reason for replacing k (gravitational constant) with Rv .... any ideas?

It is puzzling matter, this author keeps me thrown in confusion...
Was this from a book or journal article? Could you give us a citation?
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