Practice mode Electrostatics

Two charges are moved from air into water of relative permittivity 80 while their separation stays the same. The force between them becomes ____.

Correct answer D. 1/80 of its value in air

Explanation

In a medium F = kq₁q₂/(εᵣr²). Water's large relative permittivity of 80 reduces the force to one-eightieth of its value in air at the same separation.

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Two charges are moved from air into water of relative permittivity 80 while their separation stays the same. The force between them becomes ____.

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Two charges are moved from air into water of relative permittivity 80 while their separation stays the same. The force between them becomes ____.

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