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Hydraulic pressure links pistons through fluid

Pressing a hydraulic brake pedal changes pressure in fluid-filled lines. That pressure can transmit force to pistons at the wheels, while piston area affects the force produced. Explore Pascal's principle with a simple pair of pistons before considering the extra components in a real braking system.

4–5 min

Questions you could explore

  • Why can two pistons experience the same pressure but different forces?
  • What happens to the distance each piston moves when their areas differ?

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