Only during landing and takeoff. Cell phones interfere with their radio communication. The phones are really the problems but don't use any technology on landing or takeoff because the flight attendants will give you a dirty look and ask you to turn it off
A component switch is used with electronics and wiring. You can wire electronics to turn on using a switch with multiple linked to one. A component switch is the overall central one that they all link to and function off of.
You could just switch off the switches in the fuse box
A switch is a means of making (on) or breaking (off) an electrical circuit.
Battery is disconected
Its all electronics. Either turn your fuel pump off manually by cutting power supply. In practice, when you turn switch off, hdi pump and injectors stop as well. There is no mechanical valve.
check the connection where the battery plugs into the under hood fuse block check the connection at the starter and check your ignition switch,(im not sure what you mean by electronics everything including engine or just the radio and stuff)
The binary number system inside the electronics of a computer is generally represented by a high or a low voltage, a charged or uncharged capacitor, or sometimes even a switch that is on or off. That these electronics are generally in either one or the other state, the binary system is the simplest.
Sounds like a funky kill switch or safety switch.
No, but it may be allowed in the hold. Not all countries allow these on or off flights
Switch it off and wait 5mins then switch it back on again 
A main switch is one which controls all the electrical power at a given house or other location. That's what is meant by main switch.
It is used to run computers. The computer either has a switch on(1) or switch off(0). It is used in most electronics like computers, calculators, and to circulate electriciy.