It depends on the computer. For example, a tablet can run for a very long time without a fan, so they don't even have fans. Many high quality desktops have liquid cooling. In a laptop or a low quality desktop, it won't run very long without a fan, especially if it's working hard. Maybe a couple seconds?
You can run it until the processor overheats and shuts down which will not take long. Eventually the processor ECU will fail due to overheating and you will be replacing it.
the computer will freeze or the fan will run automatically!
Yes you can... you can run DVD's, Games, CD's on a computer without internet.
Yes
The fan on a home computer should run constantly to keep everything cool. Fans will typically adjust their speed based on temperatures, but only turn off when the computer goes to sleep or is shut down.
If the fan is not working - your computer is more than likely to be overheating - causing the processors to run slowly. Without being fixed, the lack of cool airflow from the fan will cause irreparable (and thus expensive) damage to your computer.
It is not stated what fan is being used? Assuming it is a cooling fan used in a computer: the fan usually blows hot air out of the computer through exhaust vents, drawing in cold air from other vents.
absolutely
It might be a bad power supply that only sends the correct voltage type to run a fan but not a mother Bord or hard drive.
The computer uses the engine coolant temp sensor to decide when to run the fan.
unplug the coolant sensor and turn on the ignition without starting the engine. The fan will run.
Yes.