Randall D. Knight — Impulse and Momentum: Problem 45

Most geologists believe that the dinosaurs became extinct 65 million years ago when a large comet or asteroid struck the earth, throwing up so much dust that the sun was blocked out for a period of many months. Suppose an asteroid with a diameter of 2.0 km and a mass of \(1.0 \times 10^{13} \text{ kg}\) hits the earth (\(6.0 \times 10^{24} \text{ kg}\)) with an impact speed of \(4.0 \times 10^4 \text{ m/s}\). a. What is the earth’s recoil speed after such a collision? (Use a reference frame in which the earth was initially at rest.) b. What percentage is this of the earth’s speed around the sun? The earth orbits the sun at a distance of \(1.5 \times 10^{11} \text{ m}\).