Answer: Option [A]Psychrometer is an instrument used to measure relative humidity of air. A psychrometer measures the relative humidity in the atmosphere through the use of two thermometers: a dry bulb thermometer, is used to measure the temperature by being exposed to the air. a wet bulb thermometer, measures temperature by having the bulb dipped in a liquid.
Answer: Option [A]The correct answer is tropical air meets cold polar air. Frontal rain occurs in places where air masses from tropical areas and polar areas meet. However, like when you're climbing a hill, the higher you go up in the atmosphere, the colder it is. So the warm air that has risen up in the atmosphere now begins to cool down.
Answer: Option [D]The contact of two air masses differing sharply in humidity originates temperate cyclones. The contact of two air masses differing sharply in humidity originates temperate cyclones. Temperate Cyclones also called mid-latitudinal cyclones or extra tropical cyclones are formed due to interaction of air masses of different temperature.
Answer: Option [C]The correct answer is due to air pollution. Smog is formed by mixing air with pollutants and exhaust gases resulting from human activities. The factors which are responsible for this include factories, an increasing number of cars, burning coal, wood and other solid fuels in stoves.
Answer: Option [C]In the Earth's atmosphere, the atmospheric pressure decreases with height. This is because at higher altitudes number of air molecules present are low when compared to those that are present in the lower atmosphere. Moreover gravitational pull which is responsible for atmospheric pressure is low on the molecules that are away from its surface than those that are closer to it.