The correct option is 1 and 3 only.
Explanation
Evaporation is the physical process by which a substance transitions from a liquid state to a gaseous state. It is a crucial element of the hydrological cycle and is influenced by factors such as temperature, surface area, humidity, and wind speed.
Statement-wise Analysis:
- Statement 1 is Correct: Evaporation is the process by which water is transformed from a liquid to a gaseous state (water vapour). Heat energy is absorbed during this process (latent heat of vaporization).
- Statement 2 is Incorrect: The temperature at which a given sample of air becomes saturated with moisture is called the dew point. At the dew point, the air cannot hold more moisture, and condensation (transformation from gas to liquid) begins. Evaporation, conversely, can occur at various temperatures and is not defined by the dew point.
- Statement 3 is Correct: The movement of air (wind) significantly affects the rate of evaporation. When air is calm, the layer immediately above a water surface becomes saturated with vapour, slowing down the process. Wind replaces this saturated layer with unsaturated (drier) air, thereby maintaining the moisture gradient and increasing the rate of evaporation.
Key Takeaway:
Evaporation involves the change of state from liquid to gas and is enhanced by air movement and heat. The dew point is the specific temperature at which air reaches saturation, leading to condensation.