Patricia Bean

2022-07-17

On the atomic or molecular scale, why gravitational forces play no role because electric forces are enormously stronger?

sviudes7w

Gravity is the weakest force among all the fundamental forces. In atomic or molecular scale the gravitational attraction force is very weak. The atomic particles like protons, neutrons, electron have a mass in the order of . The gravitational force is proportional to the mass of the particles.
Quantitatively let us calculate the gravitational force and the electric force between two protons.
Mass of proton,
Charge of proton,
Distance between two protons is, approximately.
Gravitational force is given by,
${F}_{g}=G\frac{m\cdot m}{{r}^{2}}$ (1)
Where, G is the gravitational constant having value of $6.674×{10}^{-11}\frac{{m}^{3}}{kg\cdot {s}^{2}}$
Substituting the values in equation (1) we get,
${F}_{G}=6.674×{10}^{-11}×\frac{1.67×{10}^{-27}×1.67×{10}^{-27}}{\left(1.2×{10}^{-16}{\right)}^{2}}N\phantom{\rule{0ex}{0ex}}⇒{F}_{G}=1.29×{10}^{-32}N$ (2)
Electric force is given by,
${F}_{e}=k\frac{q\cdot q}{{r}^{2}}$ (3)
Where, k is the coulomb’s constant having a value of $9×{10}^{9}\frac{N\cdot {m}^{2}}{{C}^{2}}$
Substituting the values in equation (3) we get,
${F}_{E}=9×{10}^{9}×\frac{1.6×{10}^{-19}\cdot 1.6×{10}^{-19}}{\left(1.2×{10}^{-16}{\right)}^{2}}N\phantom{\rule{0ex}{0ex}}⇒{F}_{E}=1.6×{10}^{4}N$ (4)
From the values of gravitational force and the electric force between two protons it is clear that the gravitational force is very weak in atomic scale and electric force is very strong.

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