If you've ever put gas in a car, you've probably noticed how the gas pump shuts off when your tank is full. But how does it know to do that? Learn more about the clever mechanism that keeps your gas tank from overflowing in this episode of BrainStuff.

Whether the topic is popcorn or particle physics, you can count on the HowStuffWorks team to explore and explain the everyday science in the world around us on BrainStuff.

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