Question

★ Define Coulomb's Law

Answer 1

Coulomb's Law : –

According to Coulomb's Law , the force of interaction between any two point charges is directly proportional to the product of the charges and inversely proportional to the square of the distance between them .

$\boxed{\sf{F = K \dfrac{q_{1} q_{2}}{r^{2}}}}$

Here, K is electrostatic force constant .

Coulomb's law is not applicable in all situations, it is applicable under the following conditions –

The electric charge must be at rest.

The electric charges must be point charges, means size of charges must be stronger than the separation between the charges.

Answer 2

Coulomb's Law of Electrostatic Forces : –

According to Coulomb's Law of electrostatic forces, the force of interaction between two point charges is directly proportional to the product of magnitude of charges and inversely proportional to the square of the distance between them .

According to Coulomb's Law ,

$\rightarrow \: \sf{ F \propto q_{1} \: q_{2} } - - - - (1)\\ \\ \rightarrow \: \sf{ F \propto \dfrac{1}{ {r}^{2} } } - - - - - (2) \\ \\ \sf{combining \: these \: two \: relations :- } \\ \\ \rightarrow \: \sf{F \propto\: \dfrac{q_{1} \: q_{2}}{r^{2}}} \\ \\ \rightarrow \: \underline{\fbox{\sf{F = K \: \dfrac{q_{1} \: q_{2}}{r^{2}}}}}$

Where, K is constant and is known as electrostatic force constant .

Coulomb's law of electrostatic force between two charges corresponds to Newton's law of gravitation and force between masses .

$\rightarrow \: \underline{\fbox{\sf{F = G \: \dfrac{m_{1} \: m_{2}}{r^{2}}}}}$

Where, G is constant and is known as gravitational constant .