What is the kinetic energy of a 5 kg body moving at 12 m/s?
Answer and explanation
Correct answer: C. 360 J
- Step 1: KE = ½mv². Step 2. KE = ½ × 5 × 12² = 360 J. Answer: 360 J. Why not the others: 720 J is what you get if you forget the factor ½. 30 J is what you get if you forget to square the speed. 180 J is what you get if you halve twice.
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