Question

Two point charges are brought closer together, increasing the force between them by a factor of 17. By what factor was their separation decreased? In other words, if r1 is the original separation and r2 is the final separation, what is the ratio r1/r2?

Answer 1

Answer:

$\dfrac{r_1}{r_2}=4.123$

Explanation:

Given:

Final force between them=17(initial force between them)

initial separation between them $r_1$

Final separation between them $r_2$

Let Q and q be the charges on them then

$F_2=17F_1\\\dfrac{kQq}{r_2^2}=17\dfrac{kQq}{r_1^2}\\\dfrac{r_1^2}{r_2^2}=17\\\dfrac{r_1}{r_2}=4.123$