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Question
What is an electroscope? Describe the different stages of charging a gold leaf electroscope negatively with the help of a diagram.
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Solution
An electroscope is a device used to detect the presence of charge and the nature of a charge on the body.

The four stages of the charging a gold leaf electroscope by induction are :
(i) Bring a positively charged rod near the cap of an electroscope. The cap will acquire a negative charge on it by induction. The leaves will diverge
(ii) Earth the electroscope by touching the cap will finger.
(iii) Remove the finger and keep the positively charged rod as such.
(iv) Now, take away the rod. The leaves will diverge because of charges induced by induction.

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