Question

Two identical charges 5uc each are in the air what is the largest charge to be transferred from one charge to other so their interaction force decreases to 2.5times​

Answer 1

Answer:

Explanation:

$q_1=5\ \muC$

$q_2=5\ \muC$

Force is directly proportional to square of charges i.e.

$F_1=kq_1\times q_2$

when charge is transferred then charges become $Q_1$ and $Q_2$

such that new force decreases to $2.5$ times of original

$F_2=\frac{F_1}{2.5}=kQ_1Q_2$

such $q_1+q_2=Q_1+Q_2$

Force decrease to $2.5$ when product of $Q_1Q_2$ becomes 10[/tex]

Using hit and trial if $Q_1=8\ \muC$ and $Q_2=2\ \muC$

$Q_1\times Q_2$ becomes $16$

when $Q_1=8.75\ \muC$ , $Q_2=1.25\ \muC$

$Q_1\times Q_2$ becomes $10.93$

when $Q_1=9\ \muC$ , $Q_2=1\ \muC$

$Q_1\times Q_2$ becomes $9$

so $Q_1$ must be greater than $8.75\ \muC \text{and less than}\ 9\ \muC$

and $1\ \muC<Q_2<1.25\ \muC$ or vice-versa