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An experiment with air pressure.

  1. Feb 24, 2013 #1
    Im at work and i have a heated fan by my side. I decided to do a small experiment with air pressure. I placed a piece of paper at the back of the fan to block in coming air and the whole fan shut off and wouldn't come back on for 5 minutes. What happened inside the fan that made it turn off? If it was a circuit breaker, wouldn't it just turn back on immediately after i removed the paper?
  2. jcsd
  3. Feb 24, 2013 #2
    The reduced air flow caused the fan to over heat, and it has a thermal switch to protect it. It then takes some time for the switch to cool down and reset. Same think happens with hair dryers - we used them dry boots, and you had to fan a way that alloed enough air flow to prevent a shut off.
  4. Feb 25, 2013 #3
    The heat has to be dissipated in order to keep everything working within the fan. So if you place the paper behind, it reduces the flow of air thus causing fan to over heat. So, you need some time for it to cool and to reset.
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