When a negatively charged rod is brought near the cap of a charged gold leaf electroscope which has positive charges, the leaf
Answer Details
When a negatively charged rod is brought near the cap of a charged gold leaf electroscope which has positive charges, the electrons in the gold leaf are repelled by the negatively charged rod.
As a result, the electrons move away from the cap of the electroscope, and this causes the gold leaf to become negatively charged. The negatively charged gold leaf is then attracted to the positively charged cap of the electroscope, causing the gold leaf to collapse towards the cap.
Therefore, the correct option is "collapses".
If the negatively charged rod is removed, the electrons in the gold leaf return to their original positions and the gold leaf returns to its original state. However, if the negatively charged rod is brought close to the electroscope again, the same process will repeat, and the gold leaf will collapse towards the cap again.
Therefore, the option "collapses and diverges again" is also correct, but it is not the immediate response to the presence of the negatively charged rod.
In summary, when a negatively charged rod is brought near the cap of a charged gold leaf electroscope which has positive charges, the gold leaf collapses towards the cap due to the repulsion of electrons in the gold leaf.