Meteor Crater.? About 50,000 years ago, a meteor crashed into the earth near present-day Flagstaff, Arizona. Measurements from 2005 estimate that this meteor had a mass of about 1.4 X 108 kg (around 150,000 tons) and hit the ground at a speed of 12 km/s. (a) How much kinetic energy did this meteor deliver to the ground? (b) How does this energy compare to the energy released by a 1.0-megaton nuclear bomb? (A megaton bomb releases the same amount of energy as a mil-lion tons of TNT, and 1.0 ton of TNT releases 4.184 X 109 J of energy.)
Solution 15E Step 1 of 4: In the given problem, a meteor crashed onto the earth with a mass m=1.4× 10 kg and8 speed v= 12 km/s. Using this given data we need calculate the kinetic energy delivered by meteor to the surface of the earth and we need to compare this with the energy released by a 1.0-megaton nuclear bomb. Given data, 8 Mass of meteor , m= 1.4× 10 kg Velocity , v=12 km/s 3 3 Using 1 km =10 m v=12× 10 m/s To find, Kinetic energy , KE= Step 2 of 4: To calculate the kinetic energy delivered to the earth surface, By law of conservation of energy, the energy lost by the meteor will be equal to the amount of energy delivered to the earth surface. Kinetic Energy, KE= mv1 2 2 Where m is the mass and v is velocity of the object. 8 3 Substituting m= 1.4× 10 kg and v=12× 10 m/s KE= (1.4 × 10 kg)(12 × 10 m/s) 2 2 16 KE = 1.01 × 10 J 16 Therefore, the kinetic energy delivered to the earth surface is 1.01 × 10 J .