Ans. CHARGING THE ELECTROSCOPE NEGATIVELY
In order to change the electroscope negatively, bring a positively charged rod near the disk of the electroscope. Negative charge will appear on the disk of the electroscope while positive charges will shift to the leaves. Now connect the disk of electroscope to the earthed aluminium foil by a conducting wire. Charge of the leaves will flow to the earth through the wire. Now if we first break the earth connection and then remove the rod, the electroscope will be left with negative charge.
connection and then remove the rod, the electroscope will be left with negative charge.
CHARGING THE ELECTROSCOPE POSITIVELY
In order to charge the electroscope positively, touch the disk of electroscope with the positively charged glass rod. The charge of the rod will be neutralized as some electrons from the disk will be shifted to the glass rod leaving the disk with excess of positive charges. Now remove the glass rod from the disk, electroscope will become positively charged.