What is the kinetic energy of a 8 kg object moving at 3 m/s?
Answer and explanation
Correct answer: C. 36 J
- Step 1: Kinetic energy = 1/2 x mass x speed squared.
- Step 2: 1/2 x 8 x 3 squared = 36 J.
Answer
36 J.
Why not the others: 72 J: the factor one half was left out. 12 J: the speed was not squared. 18 J: an extra factor of one half was applied.
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