# Coulomb's Law

What will be the force on charge $$q_2$$ due to another charge $$q_1$$ separated by distance $$r$$ in a medium with relative permittivity $$\epsilon_r$$?

Details and Assumptions

• $$\epsilon_0$$ is permittivity of vacuum
• $$\hat{r_{12}}$$ is unit vector in the direction of $$q_1$$ with respect to $$q_2$$ and vice-versa.
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