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What if an Asteroid Hit the Earth?Problem: Solution:
= 5000 kg/m^{3}.
Then, the mass of the asteroid is (5000
kg/m^{3}) x
(5000 m)^{2} x (10,000 m) = 4 x 10^{15} kg
and the kinetic energy, traveling at 30,000 mph (= 1 x 10^{4} m/sec) is (1/2)
x (4 x 10^{15} kg) x (1 x 10^{4} m/sec)^{2} =
2 x 10^{23} joule.
Now, one megaton of TNT delivers 4.2 x 10^{15} joule, so that the required energy in megatons of TNT is 5 x
10^{7} megatons
or 50 million megatons! The time for the asteroid to impact the earth is (10,000
m)/(1 x 10^{4} m/sec) = 1 sec
so that the rate of energy dissipation in watts is 2 x
10^{23} watts,
or 200 billion trillion watts!!! Afterthought: |
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