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Relative Humidity Formula:
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Relative humidity (RH) is the ratio of the current amount of water vapor in the air to the maximum amount the air can hold at that temperature, expressed as a percentage. It indicates how close the air is to saturation.
The calculator uses the relative humidity formula:
Where:
Explanation: The formula calculates what percentage the actual water vapor pressure is of the maximum possible vapor pressure at that temperature.
Details: Relative humidity is crucial for weather forecasting, climate studies, HVAC system design, industrial processes, agriculture, and human comfort assessment. It affects evaporation rates, plant growth, and material preservation.
Tips: Enter actual vapor pressure and saturation vapor pressure in Pascals (Pa). Both values must be positive, and actual vapor pressure cannot exceed saturation vapor pressure.
Q1: What is the difference between relative humidity and absolute humidity?
A: Relative humidity is a percentage of saturation, while absolute humidity is the actual mass of water vapor per volume of air (g/m³).
Q2: How does temperature affect relative humidity?
A: As temperature increases, air can hold more moisture, so relative humidity decreases if moisture content remains constant. As temperature decreases, relative humidity increases.
Q3: What are typical relative humidity ranges?
A: Comfortable indoor RH is 30-50%. Below 30% can cause dry skin and respiratory issues, above 60% can promote mold growth and feel muggy.
Q4: How is saturation vapor pressure calculated?
A: Saturation vapor pressure can be calculated using various formulas like the Magnus formula or Antoine equation based on temperature.
Q5: Why is relative humidity important in weather forecasting?
A: RH helps predict precipitation, fog formation, and is crucial for understanding atmospheric stability and weather patterns.