Once Ram's mother Sunita went to her friend's home along with Ram. On visiting there,Ram saw a wet khus-khus screen hung at the door of the room. He asked his mother why they had hung this screen,and his mother answered that it keeps the room cool. Ram was satisfied and smiled.
$(a)$ According to you,what qualities are possessed by Ram?
$(b)$ How does a wet khus-khus screen hung at the door keep the room cool?

(N/A) The qualities possessed by Ram are:
$(i)$ Keen observation skills.
$(ii)$ Curiosity to learn from elders.
$(iii)$ Respectful and communicative relationship with his mother.
$(b)$ $A$ wet khus-khus screen keeps the room cool due to the process of evaporation. When the air passes through the wet screen,the water present in the khus-khus absorbs heat from the incoming air to undergo phase change (evaporation). As the air loses heat,its temperature decreases,resulting in a cooling effect inside the room.