§ 52
AERODYNAMICS.
resistance of the body, be transmitted by viscosity to the walls of the vessel, as when the body is moving quite slowly, or when the thickness of intervening fluid is small; then the resistance will
Fig. 31.
evidently follow the ordinary viscous law. When, however, the viscous drag is resisted by the inertia of the fluid, that is to say, there is no continuity of viscous stress from the body to the walls of the vessel, then it would appear probable that the law of skin-friction applies. If this view is correct, the extent of the stage
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