Specific gravity is a dimensionless quantity that compares the density or specific weight of a substance to that of a reference substance, which is typically water at 4 degrees Celsius. By taking the ratio of the specific weight of the liquid to the specific weight of water, we obtain the specific gravity of the liquid, which indicates its relative heaviness compared to water.

In hydraulic engineering, the design of the downstream glacis is crucial for energy dissipation. A slope ranging from 3:1 to 5:1 is generally considered optimal for stabilizing the hydraulic jump and maximizing the dissipation of kinetic energy, thereby reducing the potential for downstream erosion and structural damage to the spillway apron.

Mass density, commonly referred to as density, is defined as the mass of a substance per unit volume. In fluid mechanics, it is a fundamental property used to calculate the behavior of liquids and gases under various physical conditions, distinct from specific weight which involves gravitational force.

The Total Energy Line represents the total head of the fluid at any point along a pipeline or channel. According to Bernoulli's principle, this is the sum of the pressure head, the velocity head (kinetic head), and the elevation head (datum head). Monitoring the T.E.L is essential in hydraulic engineering for designing efficient irrigation systems and understanding energy losses due to friction.

Equipotential lines are imaginary lines drawn through a soil mass where the total hydraulic head remains constant at every point along the line. When combined with flow lines (stream lines) in a flow net, they allow engineers to calculate the seepage discharge, uplift pressure, and exit gradient beneath hydraulic structures like dams or weirs, which is vital for ensuring structural stability.

The hydrostatic pressure distribution on a vertical wall is triangular, with the intensity of pressure increasing linearly with depth (p = wH). The total force is the area of this pressure triangle, calculated as 0.5 * base * height, which results in 0.5 * (wH) * H, or 0.5WH^2.

Laminar flow is characterized by smooth, orderly fluid motion where particles move in parallel layers or streamlines without mixing. This type of flow occurs at low Reynolds numbers, where viscous forces dominate over inertial forces, ensuring that the path of each fluid particle remains predictable and distinct from adjacent layers.

The coefficient of discharge (Cd) is the product of the coefficient of velocity (Cv) and the coefficient of contraction (Cc). Since the coefficient of contraction is always less than unity, the coefficient of discharge is mathematically found to be lesser than the coefficient of velocity.

Bernoulli's principle is a fundamental concept in fluid dynamics that relates the pressure, velocity, and elevation of a fluid. It asserts that for an ideal fluid (incompressible and non-viscous) flowing along a streamline, the sum of pressure energy, kinetic energy, and potential energy per unit volume remains constant throughout the flow path.

The slab volume is 16 cubic meters. With a specific gravity of 0.5, the slab mass is 8000 kg. Total weight is 8400 kg (8000 + 400). By Archimedes' principle, the weight of displaced water equals the object's weight. Since water density is 1000 kg/m³, the displaced volume is 8.4 cubic meters.