What is a sensitive galvanometer?

Explanation

### Step-by-Step Solution

1. **Understanding the Galvanometer**: A galvanometer is an instrument used to detect and measure small electric currents. It consists of a coil of wire suspended in a magnetic field.

2. **Magnetic Field Setup**: In a typical galvanometer setup, there is a magnetic field created by permanent magnets. This magnetic field has a North and South polarity.

3. **Current-Carrying Loop**: Inside this magnetic field, there is a loop (or coil) through which current (I) flows. The area of this loop is denoted as A.

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