When a candle is putted into a long and deep tube the fire will go out. It because the burning fire is keeping using Oxygen, after Oxygen is burned completely, it goes out. Since after the fire completely all Oxygen in the tube, the fire goes off. However, if a along pipe is showed above the fire, the first will keep burning and never goes out because the pipe sends unburn gas out off the tube and out pressure pushes more Oxygen goes into tube. Taking out the pipe, the fire goes out.
If a fire is pushed in a closed can and let it free fall, what will happen? The flame goes down because during the can is free falling, the few Oxygen moves up; however, there is not all Oxygen leaves down side, most of them are still on the down of can with fire. But the concentration of Oxygen decrease, and it effect the flame to be darker.
The experiment of work done by the change in volume and pressure. By the the formula W= ∫PdV and PV=nRT, the formula Q=P1V1ln(V2/V1) could be found. In the experiment, In the experiment, the temperature is constant, so the U (internal energy) does not change, Since the heat is added into system is equal to the work to change volume(W=Q)
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