As hot air rises up, it reaches region of reduced pressure. The air suffers adiabatic expansion. From first law of thermodynamics
AQ = AU + AW
For adiabatic process
AQ =0
AU + AW = 0
Since, AU becomes negative. Therefore, air becomes cool.
As hot air rises up, it reaches region of reduced pressure. The air suffers adiabatic expansion. From first law of thermodynamics
AQ = AU + AW
For adiabatic process
AQ =0
AU + AW = 0
Since, AU becomes negative. Therefore, air becomes cool.