- #1
thinkingcap81
- 27
- 2
Hi,
I have a hypothetical question:
We have a fan which has no internal dissipation - electrical or mechanical. The fan is made to run in an adiabatically sealed room.
The internal energy of the air in the room increases due to work input. This work input increases the temperature and pressure of the air in the room.
So the question is: Is the increase in internal energy majorly due to (a) frictional effects between the fan blades and air molecules or, (b) due to momentum transfer to the air molecules?
Suppose there was no friction, then would the temperature and pressure of the air increase due to momentum transfer? If not what happens to the input work?
I have a hypothetical question:
We have a fan which has no internal dissipation - electrical or mechanical. The fan is made to run in an adiabatically sealed room.
The internal energy of the air in the room increases due to work input. This work input increases the temperature and pressure of the air in the room.
So the question is: Is the increase in internal energy majorly due to (a) frictional effects between the fan blades and air molecules or, (b) due to momentum transfer to the air molecules?
Suppose there was no friction, then would the temperature and pressure of the air increase due to momentum transfer? If not what happens to the input work?