A/ An ________ is a device used to detect weak currents in circuits.

Options

A. Electrolysis
B. LED
C. Electroplating
D. Electrode

Answer

**Step-by-Step Text Solution:**

1. **Understanding the Question**: The question asks for a device that is used to detect weak currents in circuits.

2. **Identifying Possible Devices**: The options provided include electrolysis, electrode, and electroplating. We need to analyze these terms to find the correct device.

3. **Defining the Terms**:
- **Electrolysis**: This is a chemical process that uses electricity to drive a non-spontaneous reaction. It is not a device.
- **Electrode**: This is a conductor through which electricity enters or leaves an object, but it is not a device specifically for detecting current.
- **Electroplating**: This is a process that uses electrolysis to deposit a layer of metal onto a surface. It is also not a device.

4. **Identifying the Correct Device**: The video mentions that the device used to detect weak currents is an LED (Light Emitting Diode). An LED can indicate the presence of current by emitting light when current flows through it, making it suitable for detecting weak currents.

5. **Conclusion**: Therefore, the answer to the question is "LED".

**Final Answer**: A/An **LED** is a device used to detect weak currents in circuits.

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