1. The problem statement, all variables and given/known data An object is free to move on a table, ex- cept that there is a constant friction force f that opposes the motion of the object when it moves. If a force of 10 N pulls the object across the table, the acceleration is 2 m/s2. If a force of 20 N pulls the object across the ta- ble, the acceleration is 6 m/s2. What is the force of friction f? a) 3.33 N b) 1 N c) 5 N d) 10 N e) none of these 2. Relevant equations F= ma and F= -F' and F= μS where μ= coefficient of static friction 3. The attempt at a solution i first find the mass in both case F= 10 N and a= 2m/s/s so m= F/a = 10/2 m= 5kg and again F= 20N and a= 6m/s/s so m= F/a = 20/6 m= 3.33kg what i do next.. or either i must go to F= μ S please help me to solve it.. how i go further?