When placed at a separation of 20 cm , two charged particles exert a Coulomb force of 20 N on each other. Determine the force if the separation is increased to 25 cm .

Step-by-step solution

According to Coulomb's law, the electrostatic force between two point charges is inversely proportional to the square of the distance between them, i.e., F 1 r^2 . Therefore, F₂ F₁ = ( r₁ r₂ )^2 Given F₁ = 20 N , r₁ = 20 cm , and r₂ = 25 cm . Substituting the values: F₂ = 20 ( 20 25 )^2 F₂ = 20 ( 4 5 )^2 F₂ = 20 16 25 = 64 5 = 12.8 N