The ratio of the forces between two small spheres with constant charge $(a)$ in air $(b)$ in a medium of dielectric constant $K$ is
The ratio of the forces between two small spheres with constant charge $(a)$ in air $(b)$ in a medium of dielectric constant $K$ is
- A
$1 : K$
- B
$K : 1$
- C
$1:{K^2}$
- D
${K^2}:1$
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