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 1.4×108kg (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 million tons of TNT, and 1.0 ton of TNT releases 4.184×109J of energy.)

Explanation:

The mass of meteor = 1.4 x 10⁸ kg

and its velocity = 12 x 10³ m/s

The kinetic energy = m v²

= x ( 1.4 x 10⁸ ) x ( 12 x 10³ )² = 1 x 10¹⁶ J                    I

The energy released by 1 ton of TNT = 4.184 x 10⁹ J

The energy released by 10⁶ ton of TNT = 4.184 x 10¹⁵ J         II

Comparing I and II

The energy released by meteor is more than the double of the energy released by 1.0 megaton nuclear bomb .

electric field is a function of 1/r^2

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