1. A 280kg flatcar 21 m long is moving with a speed of 7.0 m/s along horizontal frictionless rails. A 85kg worker starts walking from one end of the car to the other in the direction of motion, with speed 1.5 m/s with respect to the car. In the time it takes for him to reach the other end, how far has the flatcar moved? 2. Relevant equations VCM= 1/mtotal X [tex]\sum[/tex] m1[tex]\Delta[/tex]r1/[tex]\Delta[/tex] t Where V= velocity t= time r= distance. I set r=0 where the worker is at the start of the flatcar and the flatcar is also at 0 3. The attempt at a solution So I have this I found t for the worker to be 56.667 using V= r/t so then I have: VCM= 1/85+280 X [tex]\sum[/tex] 85 X[tex]\Delta[/tex]21 + 280 X r2/[tex]\Delta[/tex] t Im trying to solve for r2, the distance that the flatcar travels but I don't know what VCM is. Is it equal to the speed of the flatcar?