1. What is the Barometric Formula?

The Barometric Formula calculates atmospheric pressure at a given height above sea level. It describes how pressure decreases exponentially with altitude in an isothermal atmosphere.

2. How Does the Calculator Work?

The calculator uses the Barometric Formula:

Where:

• \( P \) — Pressure at height h (Pa)
• \( P_0 \) — Sea level pressure (Pa)
• \( M \) — Molar mass of air (kg/mol)
• \( g \) — Gravitational acceleration (m/s²)
• \( h \) — Height above sea level (m)
• \( R \) — Universal gas constant (J/mol·K)
• \( T \) — Temperature (K)

Explanation: The formula assumes constant temperature and gravity with altitude, providing an approximation of pressure decrease in the atmosphere.

3. Importance of Barometric Pressure Calculation

Details: Accurate pressure calculation is crucial for meteorology, aviation, altitude measurements, and understanding atmospheric phenomena.

4. Using the Calculator

Tips: Enter sea level pressure in Pascals, molar mass in kg/mol, gravity in m/s², height in meters, gas constant in J/mol·K, and temperature in Kelvin. All values must be positive.

5. Frequently Asked Questions (FAQ)

Q1: What is the standard sea level pressure?
A: Standard sea level pressure is 101,325 Pascals (1013.25 hPa).

Q2: What molar mass should I use for air?
A: The molar mass of dry air is approximately 0.0289647 kg/mol.

Q3: How accurate is the barometric formula?
A: It provides a good approximation for altitude changes up to about 10 km, but becomes less accurate at higher altitudes due to temperature variations.

Q4: Can I use this formula for other planets?
A: Yes, but you need to use the appropriate values for gravitational acceleration and atmospheric composition for that planet.

Q5: Why is temperature measured in Kelvin?
A: Kelvin is an absolute temperature scale required for thermodynamic calculations where zero represents absolute zero.