A shock wave is created when a powerful explosion within a fluid forms a zone of extremely high pressure that propagates through the fluid faster than the speed of sound. A shock wave carries energy and can have destructive effects as it impinges on solid objects, but it decays rapidly as it moves further away from its point of origin and gradually changes into an ordinary sound wave. How does a shock wave differ from a sonic boom?
Back in the day
Khusraw, a Persian poet, philosopher, scholar, and traveler, is considered one of the great writers of Persian literature. His most famous work is the Safarnama, an account of his seven-year journey through the Islamic world, during which time he made pilgrimages to the holy shrines of Mecca and Medina and visited many cities, including Jerusalem and Cairo. The work stands out as the most authentic account of the Islamic world at that time. He traversed what distance in those seven years?
Born on a day like today
Cyrano de Bergerac was a French writer and freethinker who satirized the customs and beliefs of his time. He wrote two romances about visits to the moon that are classics of early modern science fiction and inspired later writers such as Jonathan Swift. His swaggering personality, evinced by the many duels he fought over insults to his unusually large nose, was romanticized by Edmond Rostand in the verse drama Cyrano de Bergerac. How much of the play is an accurate reflection of his life?