Hi,
I just recently noticed that the fan of my MBA kicks in, when I connect the MagSafe while it is in Sleep-Mode. Precisely for 20 seconds. Same for 5 seconds, if I pull the plug. Maybe someone can confirm this. You have to go very close with your ear to hear the fan. Why is it like this? What's the purpose? This is not a problem or anything, I question purely from interest.

I just recently noticed that the fan of my MBA kicks in, when I connect the MagSafe while it is in Sleep-Mode. Precisely for 20 seconds. Same for 5 seconds, if I pull the plug. Maybe someone can confirm this. You have to go very close with your ear to hear the fan. Why is it like this? What's the purpose? This is not a problem or anything, I question purely from interest.