How did Einstein prove atoms existed?
In 1827, the English botanist Robert Brown noticed that pollen seeds suspended in water moved in an irregular “swarming” motion. Einstein then reasoned that if tiny but visible particles were suspended in a liquid, the invisible atoms in the liquid would bombard the suspended particles and cause them to jiggle.
What is the hardest multiplication problem in the world?
The hardest multiplication was six times eight, which students got wrong 63% of the time (about two times out of three). This was closely followed by 8×6, then 11×12, 12×8 and 8×12. Pupils found 8×7 nearly as tricky as former education minister Stephen Byers, who once famously answered that particular sum incorrectly.
What are the 7 Millennium Problems?
Clay “to increase and disseminate mathematical knowledge.” The seven problems, which were announced in 2000, are the Riemann hypothesis, P versus NP problem, Birch and Swinnerton-Dyer conjecture, Hodge conjecture, Navier-Stokes equation, Yang-Mills theory, and Poincaré conjecture.
How many millennium problems are there?
seven Millennium Prize Problems
Why is Navier Stokes unsolvable?
In particular, solutions of the Navier–Stokes equations often include turbulence, which remains one of the greatest unsolved problems in physics, despite its immense importance in science and engineering. Even more basic properties of the solutions to Navier–Stokes have never been proven.
Who Solved the Navier Stokes equation?
mathematician Grigori Perelman
What is Navier-Stokes used for?
The Navier–Stokes equations are useful because they describe the physics of many phenomena of scientific and engineering interest. They may be used to model the weather, ocean currents, water flow in a pipe and air flow around a wing.
How many Navier-Stokes equations are there?
five equations
Which fluids are incompressible?
Liquids are always considered to be incompressible fluids, as density changes caused by pressure and temperature are small. While intuitively gases may always seem to be incompressible fluids if the gas is permitted to move, a gas can be treated as being incompressible if its change in density is small.