Sunday, January 31, 2016

Refraction of Light

Refraction is the bending of a wave when it enters a medium where its speed is different. The refraction of light when it passes from a fast medium to a slow medium bends the light ray toward the normal to the boundary between the two media.

First World War Erupts in Europe


On August 1, 1914, four days after Austria-Hungary declared war on Serbia, two more great European powers—Russia and Germany—declare war on each other; the same day, France orders a general mobilization. The so-called “Great War” that ensued would be one of unprecedented destruction and loss of life, resulting in the deaths of some 20 million soldiers and civilians and the physical devastation of much of the European continent.
The event that was widely acknowledged to have sparked the outbreak of World War I occurred on July 28, 1914, when Archduke Franz Ferdinand, heir to the Austro-Hungarian Empire, was shot to death with his wife by the Bosnian Serb nationalist Gavrilo Princip in Sarajevo. Over the weeks that followed, Austria-Hungary blamed the Serbian government for the attack, hoping to use the incident as justification for settling the problem of Slavic nationalism in the tumultuous Balkans region once and for all. However, as Russia supported Serbia, an Austria-Hungary declaration of war was delayed until its leaders received assurances from German leader Kaiser Wilhelm II that Germany would support their cause in the event of a Russian intervention. This assurance came on July 5; Austria-Hungary subsequently sent an ultimatum to the Serbian government on July 23 and demanded its acceptance within two days at the risk of war. Though Serbia accepted all but two of the ultimatum’s terms, and Russia declared its intention to back Serbia in the case of such a conflict, Austria-Hungary went ahead with its war declaration against Serbia on July 28, one month after the assassinations.
With that declaration, the tenuous peace between Europe’s great powers was shattered: Germany warned Russia, still only partially mobilized, that to continue to full mobilization against Austria-Hungary would mean war with Germany. While insisting that Russia immediately halt mobilization, Germany began its own mobilization; when the Russians refused the German demands, Germany declared war on the czarist empire on August 1. That same day, Russia’s ally, France, long suspicious of German aggression, began its own mobilization, urging Great Britain—the third member, along with France and Russia, of the Triple Entente alliance—to declare its support. A divided British government declined to do so initially, but events soon precipitated Britain’s move towards war as well. On August 2, the first German army units crossed into Luxembourg as part of a long-planned German strategy to invade France through neutral Belgium. France and Germany declared war against each other on August 3; that night, Germany invaded Belgium, prompting Great Britain to declare war on Germany.
For the most part, the people of Europe greeted the outbreak of war with jubilation. The great majority of people—within government and without—assumed that their country would be victorious within months, and could not envision the possibility of a longer conflict. By the end of 1914, however, well over a million soldiers of various nationalities had been killed on the battlefields of Europe, and there was no final victory in sight for either the Allies or the Central Powers. On the Western Front—the battle line that stretched across northern France and Belgium—the combatants settled down in the trenches for a terrible war of attrition, which would continue, in Europe and other corners of the world, for the next four years.

Wednesday, January 27, 2016

What was the Zimmermann Telegram

Most historians agree that American involvement in World War I was inevitable by early 1917, but the march to war was no doubt accelerated by a notorious letter penned by German foreign secretary Arthur Zimmermann. On January 16, 1917, British code breakers intercepted an encrypted message from Zimmermann intended for Heinrich von Eckardt, the German ambassador to Mexico. The missive gave the ambassador a now-famous set of instructions: if the neutral United States entered the war on the side of the Allies, Von Eckardt was to approach Mexico’s president with an offer to forge a secret wartime alliance. The Germans would provide military and financial support for a Mexican attack on the United States, and in exchange Mexico would be free to annex “lost territory in Texas, New Mexico and Arizona.” In addition, Von Eckardt was told to use the Mexicans as a go-between to entice the Japanese Empire to join the German cause.

The British cryptographic office known as “Room 40” decoded the Zimmermann Telegram and handed it over to the United States in late-February 1917. By March 1, its scandalous contents were splashed on the front pages of newspapers nationwide. Diplomatic relations between Germany and the United States had already been severed in early February, when Germany resumed unrestricted submarine warfare and began preying on U.S. vessels in the Atlantic. While many Americans remained committed to isolationism—President Woodrow Wilson had only just won reelection using the slogan, “He kept us out of war”—the Zimmerman cipher now served as fresh evidence of German aggression. Coupled with the submarine attacks, it finally turned the U.S. government in favor of entering the fray. On April 2, 1917, President Wilson abandoned his policy of neutrality and asked Congress to declare war against Germany and the Central Powers. The United States would cast its lot with the Allies four days later.


Cool Science Stuff

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Mercury, Venus, Mars, Saturn and Jupiter will be simultaneously visible to the naked eye for the first time in more than a decade.
The spectacle is visible from Wednesday until 20 February, but experts warn that Mercury will become fainter towards the end of that window.
Experts advise stargazers to begin their viewing 45 minutes before dawn.
The display is made possible by the unusual alignment of the five planets along what's known as the ecliptic plane of their orbits. In practice, this means the planets lie near the plane of Earth's orbit, projecting as a line.

Can You Really Go Back in Time by Breaking the Speed of Light?

Tuesday, January 26, 2016

Happy 179th Birthday Michigan

Happy Birthday Michigan

Click link for some fun facts about our Great State

Monday, January 25, 2016

Light Waves

In a light wave the direction of the wave, magnetic field and electric field are all perpendicular to each other.

Light as a wave and particle click here.

Diagram of Trenches in WW1