A 67.0kg- painter is on a uniform 23kg- scaffold supported from above by ropes. There is a 3.6kg- pail of paint to one side, as shown .
A 67.0kg- painter is on a uniform 23kg- scaffold supported from above by ropes. There is a 3.6kg- pail of paint to one side, as shown. I need to know how close to the right and left ends he can safely approach. As the painter moves beyond the ropes, his weight produces a torque which will cause the scaffold to rotate. Let’s chose the point where the right rope attaches to the scaffold as the pivot point. Clockwise torque = Weight * distance to the right of the right rope. Clockwise torque = 67.0 * 9.8 * d The weight of the scaffold is located at the center, which is 2 meters to the left of the pivot point. The weight of the can is located 3 meters to the left of the pivot point. Counter clockwise torque = (23 * 9.8 * 2) + (3.6 * 9.8 * 3) 67.0 * 9.8 * d = (23 * 9.8 * 2) + (3.6 * 9.8 * 3) Divide both sides by (67 * 9.8) d = 0.834 meters When the painter walks to a position that is 0.834 meter to the right of the right rope, the scaffold will begin to rotate clockwise. This will cause the paint can to slide to the right. Do the same process for the left side. This time the point where the left rope attaches to the scaffold is the pivot point. The only change is the distance of the paint can from the pivot point. The paint can is 1 meter from the left rope. 67.0 * 9.8 * d = (23 * 9.8 * 2) + (3.6 * 9.8 * 1) Solve for d! I actually did this a few summers ago. I walked beyond the rope. The scaffold rotated, and I sled down the scaffold and fell to the ground! I am glad that the scaffold was only 6 ft off the ground!
