1. The problem statement, all variables and given/known data A device consists of eight balls each of mass 0.7 kg attached to the ends of low-mass spokes of length 1.8 m, so the radius of rotation of the balls is 0.9 m. The device is mounted in the vertical plane. The axle is held up by supports that are not shown, and the wheel is free to rotate on the nearly frictionless axle. A lump of clay with mass 0.23 kg falls and sticks to one of the balls at the location shown, when the spoke attached to that ball is at 45 degrees to the horizontal. Just before the impact the clay has a speed 6 m/s, and the wheel is rotating counterclockwise with angular speed 0.10 radians/s. (a) Which of the following statements are true about the device and the clay, for angular momentum relative to the axle of the device? The angular momentum of the falling clay is zero because the clay is moving in a straight line. The angular momentum of the device is the same before and after the collision. The angular momentum of the device + clay just after the collision is equal to the angular momentum of the device + clay just before the collision. The angular momentum of the device is the sum of the angular momenta of all eight balls. Just before the collision the angular momentum of the wheel is 0. 2. Relevant equations 3. The attempt at a solution I'm pretty sure the clay has angular momentum, so I think the first one is right. I'm not sure about the second one but I don't think it's right. I think the angular momentum of the system stays the same. I think the momentum of the device is the sum of all the balls. And I don't think the angular momentum of the wheel is 0.