
Trivia: A little nod to another Blue Sky Studios Production, "Ice Age". When Rodney is looking around Robot city, he comes across a red robot that plays hip-hop. As Rodney walks away nervously ("Uh, n-n-never mind"), pause the frame just before the shot changes and you'll see (on the left) a yellow, mechanical Sid. Sid is the sloth (and the main character) from "Ice Age". (00:15:25)
Answer: Ferric metal can itself become magnetized after being exposed to a strong magnetic field (such as the one that stuck to him at Bigweld Industries. It will wear off after a short time.
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