Newtonian telescope Newtonian telescope The Newtonian telescope, also called the Newtonian reflector or just the Newtonian, is a type of reflecting telescope invented by the English scientist Sir Isaac Newton (1642–1727), using a concave primary mirror and a flat diagonal secondary mirror. Newton's first reflecting telescope was completed in 1668 and is the earliest known functional reflecting telescope. The Newtonian telescope's simple design makes it very popular with amateur telescope makers. Newton's idea for a reflecting telescope was not new. Galileo Galilei and Giovanni Francesco Sagredo had discussed using a mirror as the image forming objective soon after the invention of the
Newtonian fluid liquid, and not diagonal components – turbulence eddy viscosity. The following equation illustrates the relation between shear rate and shear stress: formula_29 Where: 𝜏 = Shear stress µ = Viscosity dV/dy = Shear rate If viscosity is constant, the fluid is Newtonian.Power Law Model The Power Law Model is used to display the behavior of Newtonian and Non-Newtonian Fluids and measures shear stress as a function of strain rate. formula_30 formula_31= Absolute Value of the Strain Rate to the (n-1) power formula_32 = Velocity Gradient n = power law index ( n =1 for Newtonian Fluids), typically n = 0.5