Acopper sphere was moving at 25 m/s when it hit another object. this caused all of the ke to be converted into thermal energy for the copper sphere. if the specific heat capacity of copper is 387 j/(kg ⋅ c°), what was the increase in temperature? 0.23 c° 0.81 c° 1.3 c° 2.1 c°

Aperson stands on a platform, initially at rest, that can rotate freely without friction. the moment of inertia of the person plus the platform is ip. the person holds a spinning bicycle wheel with its axis horizontal. the wheel has moment of inertia iw and angular velocity ωw. take the ωw direction counterclockwise when viewed from above. part a what will be the angular velocity ωp of the platform if the person moves the axis of the wheel so that it points vertically upward?