AP PHYSICS 2
SUMMARY CHAPTER 11 - FLUIDS IN MOTION
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Flow rate The flow rate Q of a fluid is the volume V of fluid that passes a cross section in a tube
divided by the time interval 𝚫t needed for that volume to pass. Flow rate also equals the product of
the average speed v of the fluid in the cross-sectional area A of the vessel.

Continuity equation a fluid does not accumulate the flow rate into a region (position 1) equal the
flow rate out of the bridges (position 2). At position 1 the fluid has speed v1 and the tube has
cross-sectional area A1. At position to this we would have stayed v2 and the two has crosssectional area A2.

Bernoulli’s equation For a fluid flowing without friction or turbulence, the some of the kinetic
energy density (½) v2, the gravitational potential energy density  g y, and pressure P of the fluid
is a constant.