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On an essentially frictionless, horizontal ice rink, a skater moving at 5.0 m/s encounters a rough patch that reduces her speed by 45 % due to a friction force that is 45 % of her weight.

Part A. Use the work-energy theorem to find the length of this rough patch. Express your answer using two significant figures.

User Vanessa
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Final answer:

To find the length of the rough patch, we can use the work-energy theorem.

Step-by-step explanation:

To find the length of the rough patch, we can use the work-energy theorem. The work done by the friction force is equal to the change in kinetic energy of the skater. The initial kinetic energy is given by (1/2)mv12, where m is the mass of the skater and v1 is her initial velocity. The final kinetic energy is given by (1/2)mv22, where v2 is her final velocity. The work done by the friction force can be calculated using the formula: work = force x distance. In this case, the force is 45% of the skater's weight, which can be calculated using the formula: force = mass x acceleration due to gravity. By equating the work done by the friction force to the change in kinetic energy, we can solve for the distance traveled on the rough patch.

User Marcw
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