The Ride "Superman, The Escape" at six flags magic mountain in california is a Linear Induction Motor driven ride that pushes the ride car using electromagnets. At both ends of the track are some serious magnets that if something fails will stop the car that has a metal fin the electromagets act on in a fail-safe way using that principle. I'm not privy to the exact details, but knew some of the designers. This was built in the mid-90s. You can see the one end in this picture. https://rcdb.com/140.htm#p=264 I've seen it in testing with a power off e-stop and the car just comes to a rather sudden halt, and they have to get it out with a winch slowly. Pretty good safe solution, though not a feature of normal ride operation.