It is a layer of air that is either warmer or colder than the layers above
and below it. It will bend the radio waves. Also in the ocean water it is
a layer of water that is warmer or colder than the water above and below it.
The sonar used to search for submarines will bend and give a false
indication of where the sub is if it even bounces off of it.
Yes. Indeed you were. Quite frankly, I am somewhat amused at the
responses to this question in this group.
Oh...The "body effect" is noted by the change in threshold voltage that
occurs when the backgate/substrate connection of the mos is connected to
a lower potential then its source (nmos case).
If the mos is an isolated structure, one can tie its local tank/well to
its source. This minimises its Vt. If the structure is a non-isolated
one, then this cant be done. In this case the effective Vt will be
higher if the source is not at the substrate potential, e.g. in a nmos
differential pair. Isolated mos use more area, so its a trade off as to
how one designs the circuit. A higher Vt usually can result in less
signal handling range.
The weather over here (London) is a bit drizzly and cold today though.