This is for a lab, I need help finding the coefficient of kinetic friction since when I solve I get a negative answer. In the lab we have a block of wood that has a downward weight of 2.12 N. It is on a ramp set at 20 degrees and we pulled it UP THE RAMP. Using the laptop and a sensor it recorded the applied force at 1.2 newtons.
coefficient of friction= force of friction/ normal force
The Attempt at a Solution
So i set the weight into components and found the one going parallel to the ramp to be .73 Newtons and the normal force to be 2. To find the force of friction I did .73- 1.2 = -.47. Then I divided that by the normal force and got -.235. Obviously that does not make sense. Usually im used to problems in which the applied force is down the ramp. So now it might be different since its going up ( and i dont know how to solve it that way). Please help, thanks