Q4A. Define the following and give their mathematical I. Density. ii. Specific weight. iii. Specific gra B. Calculate the density, specific weight and specific gra

Q4A. Define the following and give their mathematical formulas:

I. Density:
Density ($\rho$) is a measure of mass per unit volume of a substance. It indicates how much mass is contained in a given volume.

$$\rho = \frac{m}{V}$$

where $m$ is mass and $V$ is volume.

II. Specific weight:
Specific weight ($\gamma$) is the weight per unit volume of a substance. It is also the product of density and the acceleration due to gravity.

$$\gamma = \frac{W}{V} = \rho g$$

where $W$ is weight, $V$ is volume, $\rho$ is density, and $g$ is the acceleration due to gravity.

III. Specific gravity:
Specific gravity ($SG$) is the ratio of the density of a substance to the density of a reference substance (usually water at $4^\circ\text{C}$ for liquids and solids, or air for gases). It is a dimensionless quantity.

$$SG = \frac{\rho_{\text{substance}}}{\rho_{\text{reference}}}$$

where $\rho_{\text{substance}}$ is the density of the substance and $\rho_{\text{reference}}$ is the density of the reference substance. For liquids, $\rho_{\text{reference}} = 1000 \, \text{kg/m}^3$ (density of water).

Q4B. Calculate the density, specific weight and specific gravity:
The necessary data (e.g., mass, volume, or type of substance) for calculation is not provided in the image. To calculate these values, the mass and volume of the substance would be required, or its density directly.