Heat exchanged to air on a cylinder problem?

AI Thread Summary
When heat is transferred to air inside a cylinder and the volume doubles, the pressure change depends on the amount of heat added. If the heat added is sufficient to double the temperature while allowing the volume to expand freely, the pressure remains constant. However, if an excessive amount of heat is added without a corresponding increase in volume, the pressure will rise. The relationship between pressure, volume, and temperature is crucial, as it indicates that volume is proportional to temperature at constant pressure. Clarification on related thermofluids questions was also sought in the discussion.
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Homework Statement


If heat is transferred to air inside a cylinder and the volume doubles does the pressure change ?


2. Homework Equations + thoughts about the statement
My thoughts are that energy is given to the air molecules inside the cylinder causing the volume of the air to expand hence the volume double i personally think the pressure stays the same(as the cylinder moves to return the pressure to the original pressure as the heat is transferred) but i am not 100% sure of the relationship here. Can anyone shed some light on the situation?


Thanks i may have a few more queries
 
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It is a rather badly worded question, it depends on how much heat.
I suspect they are trying to say that the volume is free to expand as much as it likes to keep the pressure constant.

The relationship is the Pressure * Volume is proprtional to Temperature
If the correct amaount of heat was added to double the temperature and the volume doubled then the pressure would stay the same.
If a million times as much heat was added and the volume only doubled then the pressure would go up!
 
I thought that myself about the question a little misleading, so volume is proportional to temperature at a constant pressure meaning that if heat is added the volume will increase and the pressure remains constant. Cheers for the quick reply you don't by any chance have any ideas about the other thermofluids question i have asked? It involves a U tube manometer in a wind tunnel another question that i am really struggling to get my head around.
Cheers
 
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