where a c {\displaystyle a_{c}} is the centripetal acceleration. The direction of the force is toward the center of the circle in which the object is moving, or the osculating circle (the circle that best fits the local path of the object, if the path is not circular).
The assassination of Archduke Franz Ferdinand of Austria, heir presumptive to the Austro-Hungarian throne, and his wife Sophie, Duchess of Hohenberg, occurred on 28 June 1914 in Sarajevo when they were shot dead by Gavrilo Princip.
One hundred years ago, the heir to the throne of the Austro-Hungarian empire and his wife were assassinated by a gunman during a drive through Sarajevo. One month later, Austria-Hungary declared war on Serbia. The killing of Archduke Franz Ferdinand would trigger one of the most brutal wars in modern history, eventually pulling in the Russian Empire, Germany, France, Italy, China, the U.S., Japan and beyond into World War I.