In the coulomb's law of magnetism, force is inversely proportional to ____________.

CONCEPT:

• Coulomb's law of magnetism: It states that, If two magnetic poles of strengths m1 and m2 are held apart at a distance r then the force of attraction or repulsion between the two poles is directly proportional to the product of their pole strengths and inversely proportional to the distance square between them.

\(F = \;\frac{{{μ _0}}}{{4\;\pi }}\frac{{{m_1}{m_2}}}{{{r^2}}}\)

Where μ₀ is the permeability of free space, m₁, m₂ are pole strengths and r is the distance between two poles.

EXPLANATION:

• According to coulomb's law of magnetism, force is inversely proportional to the square of the distance. So option 4 is correct.

​Extra points:

• The strength of force increases by a factor of 100 if the charges come 10 times closer.