This was not a popular question among the candidates. Some of those candidates who answered the question drew good diagrams but could not describe the process of cloud formation. The process of cloud formation includes:
evaporation of water from earth surface and transpiration from leaves of plants;
rising of moisture laden air to high altitudes;
cooling of air on ascent;
saturation of air at dew points;
condensation around hydro scopic nuclei;
accumulation of condensed particles to form cloud.
Some of the candidates were not able to name the types of cloud. The types of cloud are:
cirrus, cirrostratus, cirrocumulus, altostratus, cumulus, stratocumulus, nimbostratus, stratus and alto-cumulus.