1. What is Specific Weight Using Equation Of State?

Specific Weight of Liquid in Piezometer is the ratio of a body's weight P to its volume V. This calculator uses the equation of state to determine specific weight based on absolute pressure, gas constant, and absolute temperature.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( S \) — Specific Weight of Liquid in Piezometer (N/m³)
• \( P_{ab}' \) — Absolute Pressure by Specific Weight (Pa)
• \( R \) — Gas Constant (J/kg·K)
• \( T \) — Absolute Temperature of Gas (K)

Explanation: The equation relates specific weight to absolute pressure, gas constant, and absolute temperature using the equation of state principle.

3. Importance of Specific Weight Calculation

Details: Calculating specific weight is crucial in fluid mechanics and engineering applications for determining buoyancy forces, pressure distributions, and fluid behavior in various systems.

4. Using the Calculator

Tips: Enter absolute pressure in pascals, gas constant in J/kg·K, and absolute temperature in kelvins. All values must be positive and valid.

5. Frequently Asked Questions (FAQ)

Q1: What is specific weight?
A: Specific weight is the weight per unit volume of a material, typically measured in N/m³ in the SI system.

Q2: How does specific weight differ from density?
A: Density is mass per unit volume (kg/m³), while specific weight is weight per unit volume (N/m³). They are related by gravity: specific weight = density × gravity.

Q3: What is absolute pressure?
A: Absolute pressure is the total pressure measured relative to a perfect vacuum (absolute zero pressure).

Q4: Why use absolute temperature in this calculation?
A: Absolute temperature (in kelvins) is used because gas laws and equations of state require temperature measurements from absolute zero.

Q5: What are typical values for gas constant?
A: The gas constant varies by gas. For air, it's approximately 287 J/kg·K. For other gases, consult thermodynamic tables.