In nonideal fluid dynamics, the Hagen–Poiseuille equation, also known as the Hagen–Poiseuille law, Poiseuille law or Poiseuille equation, is a physical law that gives the pressure drop in an incompressible and Newtonian fluid in laminar flow flowing through a long cylindrical pipe of constant cross section.
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Germany is a Western European country with a landscape of forests, rivers, mountain ranges and North Sea beaches. It has over 2 millennia of history. Berlin, its capital, is home to art and nightlife scenes, the Brandenburg Gate and many sites relating to WWII. Munich is known for its Oktoberfest and beer halls, including the 16th-century Hofbräuhaus. Frankfurt, with its skyscrapers, houses the European Central Bank.

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