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Question 7.66: If a car of mass 1200 kg is moving along a highway at 120 km......

If a car of mass 1200 kg is moving along a highway at 120 km/h, what is the car’s kinetic energy as determined by someone standing alongside the highway?

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After converting the speed: v = 120 km/h = 33.33 m/s , we find

K=\frac{1}{2}\, m v^2=\frac{1}{2}(1200 \,kg )(33.33 \,m / s )^2=6.67 \times 10^5 \,J .

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