The air inside a hot-air balloon is heated up from a density of 1.25 km/m^3 and a temperature of 27 degree celcius until the balloon begins to float . During the heating process , some air escapes from the balloon and the pressure inside the balloon remains constant at just above the atmosphric pressure . THe mass and volume of air in the balloon just before it rises are 300 kg and 400 m^3 respectively . The temperature of hot ait is ??
Charles law and Boyle's law
The Attempt at a Solution
From Charles law , v1/T1=v2/T2
so i need to find V1 first before i can get T2 , i attempt to make use the other info given .
density = m/v
is the mass of the gas still the same after the expansion ? i don think so > i am not sure how to get v1