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35 votes
35 votes
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User Medrano
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1 Answer

15 votes
15 votes

Answer:

Second choice

Step-by-step explanation:

I suppose ME is the same as POTENTIAL energy

ME = mgh = 70 * 10 * 12 = 8400j

Half way down, 4200 j is converted to Kinetic Energy

1/2 m v^2 = 4200

1/2 (70) v^2 = 4200 v = 10.95 m/s

Just before impact ALL of the 8400 j is now KE
1/2 (70)v^2 = 8400 v = 15.49 m/s

User Stefano Barbi
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