Hi...ok so i just need help to make sure i'm understanding the concepts and my answers are correct. I think i get it but i just want to make sure. Thanks!!! A spool of mass m has a string wrapped around its axle, with the string coming away from the underside of the spool. The spool is on a ramp inclined at 20° with the horizontal, as shown in the figure. There is no friction between the spool and the ramp. Assuming you can exert as much or as little force on the end of the string as you wish (always directed up the slope) which of the following situations are possible? If a situation is possible, explain the condition necessary to achieve it. If the situation is not possible, explain why it is not possible. (a) The spool remains completely motionless. My answer: This is not possible because the spool is on a frictionless incline. This means that the spool will roll of the incline. You can exert force to move it back and keep it on the incline, but it will still move. (b) The spool rotates about its center but does not move up or down the ramp. My answer: This is possible because you can exert force to pull the spool back just as it is ready to roll down the incline. (c) The spool has no rotation but moves down the ramp. My answer: This is not possible because to move down the ramp the spool will need to have rotation. i don't know how to explain these answers in more detail. any help would be appreciated! Thank you!