On February 15, 2013, a superbolide meteor (brighter
than the Sun) entered Earth’s atmosphere over
Chelyabinsk, Russia, and exploded at an altitude of 23.5
km. Eyewitnesses could feel the intense heat from the
fireball, and the blast wave from the explosion blew out
windows in buildings. The blast wave took approximately 2
minutes 30 seconds to reach ground level. (a) What was the
average velocity of the blast wave? b) Compare this with
the speed of sound, which is 343 m/s at sea level.