Which of the following represents the correct increasing order of the densities of given substances?

Options

A. Cotton `lt` Exhaust from chimneys `lt` Honey `lt` Iron `lt` Air
B. Air `lt` Exhaust from chimneys `lt` Cotton `lt` Honey `lt` Iron
C. Cotton`lt` Air `lt` Exhaust from chimneys `lt` Iron `lt` Honey
D. Air `lt` Cotton `lt` Exhaust from chimneys `lt` Iron `lt` Honey

Answer

To determine the correct increasing order of the densities of the given substances (cotton, exhaust from chimneys, honey, iron, and air), we will analyze the densities of each substance step by step.

### Step 1: Understand Density
Density is defined as the mass of a substance divided by its volume. It is typically expressed in units such as kg/m³. The formula for density (ρ) is:
\[ \text{Density} (\rho) = \frac{\text{Mass}}{\text{Volume}} \]

### Step 2: Identify Densities of Each Substance
1. **Air**: The density of air is approximately 1.225 kg/m³.
2. **Exhaust from Chimneys**: This is a mixture of gases and has a density slightly higher than air, typically around 1.5 kg/m³.
3. **Cotton**: Cotton is a fibrous material that traps air within its structure, giving it a lower density than liquids. The density of cotton is approximately 0.5 to 0.6 kg/m³.
4. **Honey**: Honey is a viscous liquid and has a density of about 1.42 kg/m³.
5. **Iron**: Iron is a solid metal with a high density, approximately 7874 kg/m³.

### Step 3: Arrange the Densities in Increasing Order
Based on the densities identified:
- Air (1.225 kg/m³)
- Exhaust from Chimneys (1.5 kg/m³)
- Cotton (0.5 to 0.6 kg/m³)
- Honey (1.42 kg/m³)
- Iron (7874 kg/m³)

Now, we can arrange them in increasing order:
1. **Air** (least dense)
2. **Exhaust from Chimneys**
3. **Cotton**
4. **Honey**
5. **Iron** (most dense)

### Final Increasing Order of Densities
The correct increasing order of densities is:
**Air < Exhaust from Chimneys < Cotton < Honey < Iron**

### Answer
The correct option is **Air < Exhaust from Chimneys < Cotton < Honey < Iron**.

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