An object moving in a liquid experiences a linear drag force: D⃗ =(bv, direction opposite the motion), where b is a constant called the drag coefficient. For a sphere of radius R, the drag constant can be computed as b=6πηR, where η is the viscosity of the liquid.
Water at 20 ∘C has viscosity η=1.0×10−3Ns/m2. Suppose a 4.4-cm-diameter, 34 g ball is shot horizontally into a tank of 20 ∘C water. How long will it take for the horizontal speed to decrease to 50% of its initial value?
An object moving in a liquid experiences a linear drag force: D⃗ =(bv, direction opposite the...
Large objects have inertia and tend to keep moving-Newton's first law. Life is very different for small microorganisms that swim through water. For them, drag forces are so large that they instantly stop, without coasting, if they cease their swimming motion. To swim at constant speed, they must exert a constant propulsion force by rotating corkscrew-like flagella or beating hair-like cilia. The quadratic model of drag given by the equation, D⃗ = (12CρAv2, direction opposite the motion), fails for very...
N5D.4 (e) and (f)
both sides of the x component of Newton's second lav v, and take the indefinite integral of both sides.) Rich- N5D.4 We have seen that the drag force between a fluid and an object moving through that fluid is proportional to 2 if the object is big and/or fast and/or the fluid is not a m ery viscous but is proportional to löl if the object is small Slo At kin d/or slow and/or the fluid...