I have this assignment to do and I am stuck on finding the force of friction acting on a curling rock. 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.