I have this assignment to do and I am stuck on finding the force of friction acting on a curling rock.(adsbygoogle = window.adsbygoogle || []).push({});

The mass is 19Kg and the acceleration is -0.2m/s^2

I calculated the force applied using F = ma

This gave me -3.8N

I let negative rep force applied

positive rep force of friction

Therefore I have 3.8N [forward]

I am not sure if I am right from here on. I think I calculated the normal force or so.

I used

Fn = ma + mg

My answer for the force of gravity was 190N so then I added the 2 together and got 186.2 since the Force applied was negative. What I find awkward is that 186.2 N is the actual Force of gravity but due to sig digits, I rounded to 2 sig digits. It is here I am lost. How will I be able to calculate the force of friction?

I don't know the co-effecient of friction either. We also need to solve for that but I think I know how to once I solve for friction. Any help will be appreciated.

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# Homework Help: Hi, need some help with friction

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