MHB Electrostatic Force: Effects of Distance

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Electrostatic force, like gravitational force, follows an inverse square law, meaning that if the distance between two charged objects is doubled, the force between them decreases by a factor of one-fourth. This relationship is described by Coulomb's Law, which states that the electrostatic force is proportional to the product of the charges and inversely proportional to the square of the distance between them. The formula for electrostatic force is \(F_e = k_e\frac{|q_1q_2|}{d^2}\). Thus, both gravitational and electrostatic forces exhibit similar behavior regarding distance. Understanding this principle is crucial for applications in physics and engineering.
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How does electrostatic force vary between two objects if the distance is doubled?

I know with gravitational force as the distance doubles the force decreases by \(\frac{1}{4}\).
 
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dwsmith said:
How does electrostatic force vary between two objects if the distance is doubled?

I know with gravitational force as the distance doubles the force decreases by \(\frac{1}{4}\).

Gravitational and Electrostatic force fields are both inverse square fields. In particular for gravity (known as Newton's Law of Universal Gravitation),

\[F_g = G\frac{m_1m_2}{d^2}\]

where $G$ is the gravitational constant, $m_1$ and $m_2$ are the masses of objects and $d$ is the distance between these two objects.

Likewise for electrostatic force (known as Coulomb's Law),

\[F_e = k_e\frac{|q_1q_2|}{d^2}\]

where $k_e$ is Coulomb's constant, $q_1$ and $q_2$ are the signed charges of the particles, and $d$ is the distance between these two particles.

So if the distance between any two particles/objects is doubled in either case, the force decreases by a factor of $\dfrac{1}{4}$.
 
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