(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

On an essentially frictionless horizontal ice-skating rink, a skater moving at 3.00 m/s encounters a rough patch that reduces her speed by 45.0 % to a friction force that is 25.0 % of her weight.

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

2. Relevant equations

KE initial + Potential Energy Initial + Work= KE Final + PE Final

3. The attempt at a solution

0.5 MV^2 + mgj + mgd = 0.5 mv^2 + mgh mass will cancel out so and h is 0

0.5 v^2 + 0.25 gd= 0.5v^2

0.5 (3^2) + 0.25 * 9.8 d= 0.5 (3^2) *.45

4.5+2.45d=2.025

d=1.01 m

i guess i do not know what im doing wrong in this problem besides the reducing the final velocity.

thanks for the help!

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# Homework Help: Work Energy Principle

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