The force between two objects, each of charge - Q is measured as + F when the objects are separated a distance 2d apart. If the charge on only one object is tripled, determine the new force between them:

Fnew = k (-3Q * (-Q)) / (2d) ²

Fnew = k * 3Q² / 4d²

Explanation:

This is Coulomb's law

F = k (q₁*q₂) / r²

F - electric force

k - Coulomb constant

q₁, q₂ - charges

r - distance of charges

Starting situation : q₁ = - Q, q₂ = - Q, r = 2d

F = k (-Q * (-Q)) / (2d) ²

F = k * Q² / 4d²

NEW FORCE : q₁ = - 3Q, q₂ = - Q, r = 2d

Fnew = k (-3Q * (-Q)) / (2d) ²

Fnew = k * 3Q² / 4d²