On an essentially frictionless, horizontal ice rink, a skater moving at 6.0 m/s encounters a rough patch that reduces her speed by 42 \% due to a friction force that is 20 \% of her weight.(adsbygoogle = window.adsbygoogle || []).push({});

Use the work-energy theorem to find the length of this rough patch.

i do: [.42 * (.5) * (6)^2]/ [.2 * 9.8]=3.85

but i get the wrong answer can anyone help, does the answer need to be negative, what am i doing wrong.

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# Work-energy theorem please help, not sure what I am doing wrong.

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