In a flame ,which part of flame is called the luminous zone ?

Options

A. Outer zone
B. Inner zone
C. middle zone
D. Top of the flame

Explanation

To determine which part of a flame is called the luminous zone, we can break down the structure of a flame into its three main components:

1. **Identify the Parts of a Flame**: A flame consists of three distinct zones:
- The **dark zone** (or inner zone)
- The **luminous zone** (or middle zone)
- The **non-luminous zone** (or outer zone)

2. **Characteristics of Each Zone**:
- The **dark zone** is the innermost part of the flame. It is black in color and is the least hot part of the flame.
- The **luminous zone** is the middle part of the flame. It is yellow in color and is moderately hot. This is the part of the flame that emits light.
- The **non-luminous zone** is the outermost part of the flame. It is blue in color and is the hottest part of the flame.

3. **Conclusion**: Based on the characteristics of each zone, the part of the flame that is referred to as the luminous zone is the **middle zone**, which is yellow in color and emits light.

Thus, the answer is that the luminous zone of a flame is the **middle zone**.