Davisson-Germer Experiment

 

In 1924 Louis de Broglie  proposed that all moving particles exhibit a degree of wave-like behavior then Thompson, Davidson and Germer have conducted experiments with fast moving electrons and found that moving particles can not go in straight line but make oscillation in their path. The electrons are accelerated by applying high voltages between the anode and cathode. But in an atom there is no force which can consistently accelerate its electrons and create “standing matter wave of electrons”.

Putting wave-particle duality on a firm experimental footing, it represented a major step forward in the development of quantum mechanics

sources :

http://hyperphysics.phy-astr.gsu.edu/hbase/quantum/davger2.html#c1

http://www.youtube.com/watch?v=bqmHkQC2DKg

Photoelectric Effect

The photoelectric effect explain that the different color of light  has also given different energy. It has been showed in the vacuum tube model. A plate of the metal is attached by the light to make the electron excited from the metal then the current of electron measured by the ampere meter. The red light  with the lower frequency has not given any change to the ampere meter but the blue light has made a change. The current stop flowing when the light is turned off. The energy to excited the electron was : E = hν. Most commonly observed phenomena with light can be explained by waves. But the photoelectric effect suggested a particle nature for light.

source :

 http://hyperphysics.phy-astr.gsu.edu/hbase/mod1.html#c2

http://www.youtube.com/watch?v=N7BywkIretM&feature=related

Stainless Steel Material

Stainless steel is a product of ferrous alloy metallurgical and known to it’s character as a product designed to persist from corrosion. From the name itself “stainless steel” means resist from corrosion. Namely Chromium a metal containing in this alloy that useful to resist the corrosion. Particularly about 12 % of Chromium added. Some type of stainless steel are made depend on how much percentage of material containing.

How To Make A Steel ?

There are two kind of way to make a steel. By refining the iron ore and by recycling the scrap steel. In the refining process, the iron ore, carbon, oxygen and carbon are mixed together over the blast furnace. The limestone was added to help remove the impurities, melts, and a liquid slag. Here the presence of carbon is reducing the iron oxide to liquid pig iron. The residue of the process are carbon monoxide and carbon dioxide. We can also making the scrap iron to produce the steel over the arc furnace. The heat of the arc will melt the scrap.