Ch 10 covers fluid statics (pressure, buoyancy, Pascal's law) and fluid dynamics (Bernoulli's equation, viscosity, streamline/turbulent flow) as well as surface tension and capillarity.
Pressure at depth h: P = P₀ + ρgh. Pascal's law: change in pressure is transmitted throughout the fluid (hydraulic lift: F₁/A₁ = F₂/A₂). Bernoulli's theorem: for ideal fluid flow, P + ½ρv² + ρgh = constant along a streamline. Applications: venturi meter, airplane wing lift, atomiser.
Viscosity: internal friction in fluids, F = −ηA(dv/dx). Stokes' law for sphere in fluid: F = 6πηrv. Terminal velocity: v_t = 2r²(ρ−σ)g/9η. Reynolds number Re = ρvD/η (Re < 2000: laminar; Re > 4000: turbulent). Surface tension: S = force per unit length. Capillary rise: h = 2S cosθ/ρgr (meniscus concave for water in glass).
Download: https://ncert.nic.in/textbook/pdf/keph202.pdf | Part II: https://ncert.nic.in/textbook/pdf/keph2ps.zip
An airplane wing (airfoil) is curved on top and flatter on the bottom. Air travels faster over the curved top surface. By Bernoulli's principle (P + ½ρv² = const), higher velocity means lower pressure above the wing compared to below. This pressure difference creates an upward net force (lift) that supports the plane.
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