CMOS inverter explanation (low level output)

Question

Having a simple CMOS inverter considering Vdd 5v and Vss 0v, when the input (A) is high (5V), why the output is pulled low (Q) (0V). In my understanding when a N-MOSFET has it's drain floating (in air), source to ground and Vgs > Vth will not pull the drain to ground (if there is no pull-up on output). Is there something I am missing?

Answer 1

For a N-channel MOSFET, as the name implies, if the Vgs > Vth electrons are attracted below the gate forming a channel composed of electrons proportional to the applied Vgs voltage until saturation. That said, it creates a low impedance path between Drain and Source, meaning that the Drain end is connected to the ground.