1. A 840 gm mass is moving (with no friction) constrained by a very light string to move in a circle around a fixed post. Further, the string wraps around the very narrow post, getting shorter as the mass circles around it. The mass begins at a radius of 72 cm, with a linear velocity of 38 cm/s. When the string has wrapped enough so that the radius is reduced to 26 cm, what is the linear velocity of the mass? Hint: since there are no outside torques acting on the system, angular momentum should be conserved