The device used of detecting charge (positive or negative ) on an object is called :

Options

A. stethoscope
B. telescope
C. kaleidoscope
D. electroscope

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for the name of the device used to detect whether an object has a positive or negative charge.

2. **Identifying the Options**: The options provided are:
- Option 1: Stethoscope
- Option 2: Telescope
- Option 3: Kaleidoscope
- Option 4: Electroscope

3. **Analyzing Each Option**:
- **Stethoscope**: This is a medical instrument used to listen to internal sounds of a body, not related to detecting electric charge.
- **Telescope**: This is an optical instrument used to observe distant objects, particularly in astronomy, and does not detect electric charge.
- **Kaleidoscope**: This is a tube-shaped optical instrument that creates patterns through mirrors and colored glass, unrelated to electric charge detection.
- **Electroscope**: This is a device specifically designed to detect electric charge, either positive or negative.

4. **Conclusion**: Based on the analysis, the correct answer is Option 4: Electroscope.

5. **Explanation of Electroscope**: An electroscope typically consists of a metal rod connected to two thin leaves (often made of gold). When a charged object is brought near the electroscope, it induces a charge in the leaves. If the object is positively charged, it repels the positive charges in the leaves, causing them to spread apart due to like charges repelling each other. This movement indicates that the object has a charge.

**Final Answer**: The device used for detecting charge (positive or negative) on an object is called an **Electroscope**.

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