In: Physics
-Four masses are placed along the x − a x i s as follows. A mass of 2.0 k g is placed at x = 3.0 m, a mass of 6.0 k g is placed at x = 1.0 m, a mass of 4.0 k g is placed at x = − 2.0 m, and finally a mass of 1.0 k g is placed at x = − 4.0 m. Where is the center of mass of this system of masses?
-During a certain period of time, the angular position of a point object, rotating in a circular orbit of radius 2 m, is given by θ = 5 + 4 t + 2 t 2, where θ is in radians and t is in seconds. At t = 0, what are the magnitudes of the tangential component and the radial component of the acceleration of the point object?
-The mass of a car, including its four wheels, is 1000 kg. If all wheels have the same moments of inertia as four uniform disks of the same mass [10 kg each] and size as the wheels, what fraction of the total kinetic energy of the car is due to rotation of the wheels about their axles?
-A disc-shaped pulley, of mass 12 kg and radius 0.2 m, is wrapped around by a long string with one mass connected on each end. The part of the string that is connected to the larger mass has a tension of 5.0 N, while the part of the string connected to the smaller mass has a tension of 3.5 N. What is the angular acceleration, α, of the pulley?