About 50000 years ago, a meteor crashed into the earth near present-day Flagstaff, Arizona. Recent (2005) measurements estimate that this meteor had a mass of about 1.4*10^8 kg (around 150000 tons) and hit the ground at 12 km/s.
How much kinetic energy did this meteor deliver to the ground?
How does this energy compare to the energy produced in one day by a standard coal-fired power plant, which generates about 1 billion joules per second?