Typical weight sets used for bodybuilding consist of disk-shaped weights with holes in the center that can slide onto 2.20 m long barbells. A barbell is supported by racks located a fifth of its length from each end, as shown in the figure. What is the minimum mass m of the barbell if a bodybuilder is to slide a weight with = 22.0 kg onto the end without the barbell tipping off the rack? Assume that the barbell is a uniform rod.
sum of all torques = 0
The Attempt at a Solution
I tried to make the the intersection of the barbell and the left rack the pivot point. Then I found the torque of the weight, the center of mass of the bar, and then the 2nd rack, but I came out with the wrong answer. I think I'm on the right track on how to do it, but I'm not sure where I'm messing up. Explanation would be helpful... studying for an upcoming test. Thanks!