What is the kinetic energy of a 2.0 kg object moving at 3.0 m/s?
Answer and explanation
Correct answer: A. 9 J
- Step 1: KE = 1/2 x m x v squared. Step 2. KE = 0.5 x 2 x 9 = 9 J. Answer: 9 J. Why not the others: 6 J is mv, 18 J forgets the one half and 3 J uses v instead of v squared.
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