What is the kinetic energy of a 2 kg body moving at 3 m/s?
Answer and explanation
Correct answer: B. 9 J, from (1/2) x 2 x 3^2
- Step 1: Kinetic energy is (1/2) m v^2. Step 2. (1/2) x 2 x 9 = 9 J. Answer: 9 J. Why not the others: Speed must be squared, and the factor one half must be kept.
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