Chapter 6.6, Problem 29ES

On August $10,1972$ a meteorite with an estimated mass of $4\times {10}^6\text{ kg}$ and an estimated speed of $15\text{ km/s}$ skipped across the atmosphere above the western United States and Canada but fortunately did not hit the Earth.

(a) Assuming that the meteorite had hit the Earth with a speed of $15\text{ km/s}$ , what would have been its change in kinetic energy in joules $\left(\text{J}\right)$ ?

(b) Express the energy as a multiple of the explosive energy of $1$ megaton of $\text{TNT}$ , which is $4.2\times 1015\text{ J}$ .

(c) The energy associated with the Hiroshima atomic bomb was $13$ kilotons of $\text{TNT}$ . To how many such bombs would the meteorite impact have been equivalent?