1. The problem statement, all variables and given/known data The static friction coefficient between the grippers and the ball is 0.5, and the grippers hold the ball such that they touch the middle of the ball on opposite sides. Find the clamping force required to keep the ball from slipping out, if the ball weighs 10 lb. us= 0.5 Mass of ball = 10 lb gravity = 9.81 m/s^2 Angular velocity (wd) = 5 rad/s = Angular velocity of robot arm as they are attached. 2. Relevant equations rc=4cos45 + 2sin45 = 4.243 ft Motion of point C Vc = (wr)(rc) ar=[itex]\alpha[/itex]rc an= wr^2 (rc) ac= sqrt(ar^2 + an^2) 3. The attempt at a solution Using the above equations and the givens I found the rc which I used along with wr to solve for Vc. Vc = ( 5.0 rad/s) ( 4.243 ft) = 21.2 ft/s Then solved for both components of acceleration where : at= [itex]\alpha[/itex] rc = 0 an= wr^2 x rc = 25 x 4.243ft = 106.07 ft/s^2 Then solved for magnitude which just equalled the normal acceleration ac= 106.07 rad/s^2 Currently stuck on what to do for the second part of the question. I understand that I need to do a force FBD as I am given us and the mass of the ball. Noting that the pincers touch the middle of the ball on both sides, wouldn't that mean the contact forces oppose each other ( equal and opposite direction ) ?