What is the kinetic energy of a 10 kg object moving at 3 m/s?
Answer and explanation
Correct answer: C. 45 J
- Step 1: KE = (1/2)mv^2. Step 2. KE = 0.5 x 10 x 3^2 = 45 J. Answer: 45 J. Why not the others: 90 J: this omits the factor 1/2. 15 J: this does not square the speed. 30 J: this is the momentum, not the kinetic energy.
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