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

Lilly, whos mass is 45.0 kg, is ice skating with a constant speed of 7.00 m/s when she hits a rough patch of ice with a coefficient of friction of 0.0800. How long will it take before Lilly coasts to a stop?

m=45 kg

v=7m/s

coefficient of friction=.08

2. Relevant equations

equation 1: f=(coefficient of friction) x Normal Force

equation 2: v=u+at

3. The attempt at a solution

I know that the force of friction is 35.2 N. I got this by using equation 1.

I know that Lilly is no longer going at a constant speed once she hits the rough patch of ice, so I know she is not in equilibrium, and therefore there must be some acceleration. In order to find the acceleration though, I must know the net force. I'm having trouble figuring out how to find that.

Can anyone please give me a hint on how to find the net force? Thanks in advance if you can!

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# Homework Help: Coefficient of friction/ dynamics problem

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