Jose and Denise are having a conversation about mechanical energy. Jose says that mass has no affect on an object's potential energy. Denise disagrees and believes that mass does have an affect on an object's potential energy. who is correct , Jose or Denise? Explain your answer

Suppose a wheel with a tire mounted on it is rotating at the constant rate of 2.15 times a second. a tack is stuck in the tire at a distance of 0.373 m from the rotation axis. noting that for every rotation the tack travels one circumference (a) find the tack's tangential speed. (b) what is the tacks radial acceleration?