An object of mass 3 kg moves at 4 m/s. What is its kinetic energy?
Answer and explanation
Correct answer: D. 24 J
- Step 1: KE = 1/2 m v^2. Step 2. = 1/2 x 3 x 16 = 24 J. Answer: 24 J. Why not the others: 12 J: That uses mass times speed without squaring. 48 J: That forgets the factor 1/2. 6 J: That is half of mass times speed.
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