Question

A sonic boom is caused by _____.

a sound-producing object moving toward an observer
a sound-producing object overtaking its own sound waves
a sound-producing object moving away from an observer
a sound-producing object traveling just slower than its own sound waves

Answer 1

When the plane reaches the sound barrier, it displaces the air around it at that speed. The air waves cased by an object moving faster than sound cases it to make a sound of big "boom". This is what we call sonic boom. This happens only once, the moment the plane crosses the speed of sound.

Answer 2

GOD DAMN ALIENS

Answer 3

HAHAHAHAHAHAHAHAHA Aliens? @MellowFellow231