SE 115 Lecture Notes - Lecture 2: Kilogram, Continuum Hypothesis
Document Summary
The continuum hypothesis is used for both fluids and solids. The fundamental laws of mechanics apply to both fluids and solids. Newton"s law of motion (conservation of momentum) First law of thermodynamics (conservation of energy) The constitutive law relating stress and rate of strain also apply to both. Fluids cannot sustain a shear force, i. e. a fluid under shear is always in motion. Solids can sustain a shear force; i. e. they remain static. Stress is a function of the rate of strain, thus a fluid had a dynamic" state. Stress is a function of strain, thus a solid maintains a static or quasi- static" state. Primary quantities: length l, time t, mass m basic dimensions. Mlt system: m, l, t as basic dimensions. Flt system: f, l, t as basic dimensions. British gravitational (bg) system length: foot (ft), time: second (s), force: pound (lb), temperature: fahrenheit (0f absolute temperature: rankine mass: slug, defined from newton"s second law (force=mass*acceleration) as.
