Two point charges, $Q _ { 1 }$ and $Q _ { 2 }$, are separated by a distance $R$. If the magnitudes of both charges are doubled and their separation is also doubled, what happens to the electrical force that each charge exerts on the other one?

Question

Quizplus · Accepted Answer

Doubling both charges increases the force by a factor of 4 (since force is proportional to the product of the charges), but doubling the distance reduces the force by a factor of 4 (since force is inversely proportional to the square of the distance). These changes cancel out, leaving the force unchanged.

Two Point Charges Q1Q _ { 1 }Q1​ And Q2Q _ { 2 }Q2​

Two Point Charges $Q _ { 1 }$ And $Q _ { 2 }$