# Drag (physics): Quiz

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More interesting facts on Drag (physics)

Question 1: The notion of ________ — introduced by Prandtl in 1904, founded on both theory and experiments — explained the causes of drag at high Reynolds numbers.
Boundary layerFluid mechanicsDrag (physics)Navier–Stokes equations

Question 2: In ________, and depending on the situation, atmospheric drag can be regarded as an inefficiency requiring expense of additional energy during launch of the space object or as a bonus simplifying return from orbit.
Lagrangian pointOrbital mechanicsGravity assistInterplanetary Transport Network

Question 3: The equation is attributed to ________, who originally used L2 in place of A (L being some length).
Wilhelm RöntgenWilliam Henry BraggJohn Strutt, 3rd Baron RayleighJ. J. Thomson

Question 4: wave drag (________) or wave resistance (ship hydrodynamics).
Fluid dynamicsAerodynamicsNavier–Stokes equationsBernoulli's principle

Question 5: Its use is often vague, and is usually used in a relative sense (e.g., a ________ shuttlecock has more wind resistance than a squash ball).

Question 6: In 1752 d'Alembert proved that ________, the 18th century state-of-the-art inviscid flow theory amenable to mathematical solutions, resulted in the prediction of zero drag.

Question 7: The standard equation for drag is one half the coefficient of drag multiplied by the fluid mass density, the ________ of the specified item, and the square of the velocity.
PolygonAreaSphereTriangle

Question 8: The velocity as a function of time for an object falling through a non-dense medium, and released at zero relative-velocity v = 0 at time t = 0, is roughly given by a function involving a ________ (tanh):
Taylor seriesHyperbolic functionExponential functionTrigonometric functions

Question 9: For a solid object moving through a fluid, the drag is the component of the net aerodynamic or hydrodynamic ________ acting opposite to the direction of the movement.
ForceClassical mechanicsPhysicsEnergy

Question 10: high ________, Re > ~1000), also called quadratic drag.
Strouhal numberKnudsen numberFluid dynamicsReynolds number