Astronomers estimate that a 2.0-km-diameter asteroid collides with the Earth once every million years. The collision could pose a threat to life on Earth.
(a) Assume a spherical asteroid has a mass of 3200 kg for each cubic meter of volume and moves toward the Earth at 15km/s. How much destructive energy could be released when it embeds itself in the Earth?
(b) For comparison, a nuclear bomb could release about 4.0 × 1016 J. How many such bombs would have to explode simultaneously to release the destructive energy of the asteroid collision with the Earth?