Search results
Results from the WOW.Com Content Network
Evaporation is a type of vaporization that occurs on the surface of a liquid as it changes into the gas phase. [1] A high concentration of the evaporating substance in the surrounding gas significantly slows down evaporation, such as when humidity affects rate of evaporation of water. [2]
A hygrothermograph for humidity and temperature recording Hygrometer for domestic use, wet/dry psychrometer type Thermo hygrometer displaying temperature and relative humidity. A device used to measure humidity of air is called a psychrometer or hygrometer. A humidistat is a humidity-triggered switch, often used to control a humidifier or a ...
Humidity affects thermoregulation by limiting sweat evaporation and thus heat loss. [6] Humans cannot survive prolonged exposure to a wet-bulb temperature above 35 °C (95 °F). Such a temperature used to be thought not to occur on Earth's surface but has been recorded in some parts of the Indus Valley and Persian Gulf.
Water activity is the thermodynamic activity of water as solvent and the relative humidity of the surrounding air after equilibration. As temperature increases, a w typically increases, except in some products with crystalline salt or sugar. Water migrates from areas of high a w to areas of low a w.
The heat index explains why humidity makes a difference. Have you ever checked the temperature and noticed that it "feels" several degrees hotter? The heat index explains why humidity makes a ...
In the case of an equilibrium solid, such as a crystal, this can be defined as the pressure when the rate of sublimation of a solid matches the rate of deposition of its vapor phase. For most solids this pressure is very low, but some notable exceptions are naphthalene , dry ice (the vapor pressure of dry ice is 5.73 MPa (831 psi, 56.5 atm) at ...
In ecology, it is the difference between the water vapour pressure and the saturation water vapour pressure at a particular temperature. Unlike relative humidity, vapour-pressure deficit has a simple nearly straight-line relationship to the rate of evapotranspiration and other measures of evaporation.
While the human body has thermoreceptors in the skin that enable perception of temperature, relative humidity is detected indirectly. Sweating is an effective heat loss mechanism that relies on evaporation from the skin. However at high RH, the air has close to the maximum water vapor that it can hold, so evaporation, and therefore heat loss ...