1. The problem statement, all variables and given/known data A cylindrical piston shaft weighs 250 g and is held vertically inside an actuator (We can assume actuator is a box with hollow cylindrical space to fit the piston shaft). Compressed air at 100 psi is supplied at the bottom of the actuator and is acting on the piston upwards with a force of 90 N. The coefficient of friction between the piston shaft and the inside wall of the actuator is 0.61. I need to calculate the speed by which the shaft will eject and shoot upwards from the actuator. 2. Relevant equations Net Force= ma d= ui*t+ 0.5*a*t^2 3. The attempt at a solution Net Force= 90N- 0.25*9.81 - Ff (I am not sure if this is the right way to calculate the net force. Also, not sure how to calculate the frictional force here, although I do know Ff= coeff* R) Assuming I have a net force, I can easily find the acceleration and the distance it travels in a second. Thank you so much.