Q

Which process best explains how water droplets form on the outer surface of a cold glass during a hot day?

RRB Group D, 10-Feb-26 S-2 2026
✓ Answer: B Condensation
Condensation results in the formation of water droplets on the outer surface of a cold glass during a hot day. Condensation is an exothermic process, meaning it releases heat into the surrounding environment as the gas turns into liquid. Condensation is the exact reverse of evaporation. Condensation begins at a specific temperature called the dew point. At this temperature, the air is fully saturated and cannot hold all its water vapour. As warm air rises, it cools. The water vapour in the upper atmosphere condenses around tiny dust or smoke particles to form clouds.
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