Question

Two-point charges placed in a medium of dielectric constant 5 are at a distance r between them, experience an electrostatic force ‘F’. The electrostatic force between them in vacuum at the same distance r will be ____________.

Options

• 5F

• F

• F/2

• F/5

Answer 1

Two-point charges placed in a medium of dielectric constant 5 are at a distance r between them, experience an electrostatic force ‘F’. The electrostatic force between them in a vacuum at the same distance r will be 5F.

Explanation:

`("Q"_1                 "Q"_2)/"r"  "k" = 5`            `"F" = 1/(4 piepsilon"ok") ("Q"_1 "Q"_2)/"r"^2`

`("Q"_1                 "Q"_2)/"r"`  Force in the charges in the air is

`"F"^- = 1/(4piepsilon"o") ("Q"_1 "Q"_2)/"r"^2`

k = F

= 5 F