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Initially, the electroscope is positively charged, meaning its leaves are diverged. When a negatively charged rod is brought near the knob (without touching), free electrons in the electroscope are repelled from the knob and move down to the leaves. This reduces the net positive charge on the leaves, causing them to collapse (reduce divergence). If enough negative charge is induced to neutralize the positive charge and then make the leaves negatively charged, the leaves will diverge again due to mutual repulsion of the negative charges. Thus, the leaves will first collapse and then diverge.