Chapter 7, Problem 78GP

& BIO EST Impact extinction 65 million years ago over $50\mathrm{**\#x0025;}$ of all species became extinct, ending the reign of dinosaurs and opening the way for mammals to become the dominant land vertebrates. A theory for this extinction, with considerable supporting evidence, is that a 10-km-wide $\text{1}\text{.8 }\times {\text{ 10}}^{\text{15}}\text{-kg}$ asteroid traveling at speed 11 km/s crashed into Earth. Use this information and any other information or assumptions of your choosing to (a) estimate the change in velocity of Earth due to the impact; (b) estimate the average force that Earth exerted on the asteroid while stopping it; and (c) estimate the internal energy produced by the collision (a bar chart for the process might help). By comparison, the atomic bombs dropped on Japan during World War II were each equivalent to 15,000 tons of TNT (1 ton of TNT releases $\text{4}\text{.2 }\times {\text{ 10}}^{\text{9}}\text{ J}$ of energy).