Q. Explain why it snows on high hills, while it rains lower down.
A. The temperature of the atmosphere at higher altitudes is generally below the freezing point of water. Hence, the water vapours present in the air at higher altitudes get converted into snow which collects on the hills. Lower down, the temperature of the atmosphere is above the freezing point of water. Hence, the water vapours are converted into liquid water which comes down as rain in those regions.
Q. Explain why—if you are sweating, you will feel cooler on a hot day than on a cooler moist day.
A. On a hot dry day, the perspiration gets evaporated quickly causing more cooling effect. On a cooler moist day, the rate of evaporation is comparatively little. Therefore, the cooling caused by evaporation is also less on a cooler moist day. Hence, after sweating, one feels cooler on a hot day than on a cooler moist day.