Conceivably, yes - that could work, given the right design. I ain't laughing.
Me neither.
High-speed copy machines have a switch in the chassis near the platen. When the magnet in the cover is lowered to it, the switch engages one or more electrical sequences. Ask your xerox machine's repairman about magnetic switches.
Nineteen jetliners will fall from the sky at noon one day—and everyone will ask, "How'd they do that?" :-(