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  4. <img class=img-fluid question-image alt=Question src=https://cdn.tardigrade.in/q/nta/p-qsa65y0jyh1exhg3.jpg /> Following observations are made after performing several experiments on five styrofoam balls which are suspended from insulating threads. (i) Ball A attracts B and repels C (ii) Ball D has no effect on E and attracts B (iii) Both A and E are attracted by a negatively charged rod If an electrically neutral styrofoam ball is placed nearby a charged body, it gets attracted due to induced charge. Find the charges, if any, on each ball.

Q. Question
Following observations are made after performing several experiments on five styrofoam balls which are suspended from insulating threads.
(i) Ball $A$ attracts $B$ and repels $C$
(ii) Ball $D$ has no effect on $E$ and attracts $B$
(iii) Both $A$ and $E$ are attracted by a negatively charged rod
If an electrically neutral styrofoam ball is placed nearby a charged body, it gets attracted due to induced charge. Find the charges, if any, on each ball.

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Solution:

$D$ and $E$ has no effect on each other that means they are neutral.
A repels $C$ and attracts $B$ , That means $A$ and $C$ has similar charges and $B$ has opposite charge to that of $A$ .
A negatively charged rod attracts $A$ , That means $A$ is positively charged, hence $B$ is negatively charged and $C$ is positively charged.

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