Optics: : [op-tiks] - noun. A branch of physics that studies electromagnetic radiation (for example, light and infrared radiation), its interactions with matter, and instruments used to gather information due to these interactions.Optics includes the study of sight. branch of physics that studies electromagnetic radiation (for example, light and infrared radiation), its interactions with matter, and instruments used to gather information due to these interactions.
By 1924, the National Flag Conference, under the leadership of the American Legion and the Daughters of the American Revolution, changed the Pledge's words, 'my Flag,' to 'the Flag of the United States of America.'
Fearing the entry of the United States into World War I, Germany attempted to appease the United States by issuing, on May 4, 1916, the Sussex pledge, which promised a change in Germany's naval warfare policy. These were the primary elements of the undertaking:n 1917, Germany became convinced they could defeat the Allied Forces by instituting unrestricted submarine warfare before the United States could enter the war. The Sussex pledge was therefore rescinded in January 1917, thereby initiating the decisive stage of the so-called First Battle of the Atlantic.