This isn't a homework question... I'm just trying to understand Mosfets in general. I've been reading about them, and I find them really interesting- very cool. However, I dont understand how the Vgs = Vds if the mosfet itself has resistance!? For example, I found this in a text and I fail to understand how Vout can equal 15 volts if the top mosfet has a resistance of 5k ohms.