Advertisements
Advertisements
प्रश्न
To clean their spectacles, people often breathe out on glasses to make them wet. Explain why the glasses become wet.
Advertisements
उत्तर
During exhalation (or breathing out), carbon dioxide is released along with water vapours. If one breathes out onto glass, the released water vapours collide with the surface of the glass, thereby making it cooler. As a result, the water vapours present in the air surrounding the glass condense and get attached to the glass surface. Consequently, the glass becomes wet.
संबंधित प्रश्न
Discuss how water is replenished in sea
Why does the water split on the floor disappear after some time?
Discuss with your friends.
Rain water harvesting has an important role to protect our environment.
Water becoming water vapour on heating is called evaporation.
Colour the given picture and write the correct name in the given blanks.
(Precipitation, Evaporation, Condensation, Water storage)

What are the different stages of water cycle?
State for the following whether it is due to evaporation or condensation:
Fog appearing on a cold winter morning.
Water vapour condenses to form tiny droplets of water in the upper layers of air where it is cooler.
______ of our brain’s mass consists of water.
The water vapour gets cooled and changes into tiny water droplets that form ______ in the sky.
