A system consists of 10 0.50-kg balls, each moving radially outward from a common center in a symmetrical pattern, all at a speed of 12 m/s. What is the kinetic energy of the system?(adsbygoogle = window.adsbygoogle || []).push({});

My instinct is to say 0, since it it symmetrical and every ball moving one direction will be cancelled by a ball of the same mass and speed moving the opposite direction.

But energy is a scalar, right? And scalars only have magnitude, not direction, right?

So the answer could be

[tex]e_k=10*\frac{1}{2}mv^2[/tex]

[tex]e_k=10*\frac{1}{2}0.50kg *(12m/s)^2[/tex]

[tex]e_k=360 J[/tex]

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# Homework Help: Kinetic energy

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