What happens when a positive rod touches an electroscope?

Explanation

### Step-by-Step Solution:

1. **Understanding the Electroscope**: An electroscope is a device used to detect electric charge. It typically consists of a metal rod connected to two thin metal leaves (often made of gold or aluminum) that hang down inside a glass container.

2. **Initial Condition**: Initially, the electroscope is neutral, meaning it has an equal number of positive and negative charges. The leaves hang straight down because there is no net charge to cause them to repel each other.

3. **Bringing the Positive Rod Close**: When a positively charged rod is brought close to the electroscope (without touching it), the negative charges in the electroscope are attracted towards the rod, while the positive charges are repelled. This causes the leaves to move slightly apart, indicating that the electroscope is now charged.

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