Mechanical devices mostly symbolize the parts, joints, rigid structures in it... they mostly symbilize the tough mechanical components therefore call as mechanical :)
a zapping device is like a taser it can send a electric impulse into something like a human or animal to stun it. a electro magnetic device is something police will use to see if you have any metal...
This seems like a question from an electrical course, and is probably best answered by your course materials. It's your test question, not ours, and there won't always be someone else to ask for the...
The mechanical devices used in the Globe Theatre were things like trap doors and things that made people flying or made them come up from under the ground like hanging wires.