Imagine two pairs of shoes.
In the first pair, two shoes of mass m_1m
1
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m, start subscript, 1, end subscript and m_2m
2
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m, start subscript, 2, end subscript are separated by the distance rrr, resulting in a gravitational force F_1F
1
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F, start subscript, 1, end subscript.
In the second pair, two shoes of mass 3m_13m
1
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3, m, start subscript, 1, end subscript and 3m_23m
2
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3, m, start subscript, 2, end subscript are separated by the distance rrr, resulting in a gravitational force of F_2F
2
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F, start subscript, 2, end subscript.
The relationship between these two forces can be written as F_2 = nF_1F
2
​
=nF
1
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F, start subscript, 2, end subscript, equals, n, F, start subscript, 1, end subscript.
In the expression F_2 = nF_1F
2
​
=nF
1
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F, start subscript, 2, end subscript, equals, n, F, start subscript, 1, end subscript, what is the value of nnn?