what causes sonic boom
A sonic boom is the sound produced when an object breaks the sound barrier i.e when it travels faster than the speed of sound. When a body travels below the speed of sound (subsonic), the sound emitted by it travels in all directions.
ATLANTIC CITY, N.J. (WPVI) --. Officials say sonic booms heard and felt along the coast from New Jersey to Connecticut were caused by military fighter jets conducting tests. A Navy spokeswoman says an F-35C and F-18 from Naval Air Station Patuxent River, Maryland, were conducting supersonic testing off the coast Thursday afternoon.