A 2-lb block rests on the smooth semicylindrical surface at A. An elastic cord having a stiffness of k = 2 lb>ft is attached to the block at B and to the base of the semicylinder at C. If the block is released from rest at u = 0, A, determine the longest unstretched length of the cord so the block begins to leave the semicylinder at the instant u = 45. Neglect the size of the block.

PY 205 Daniel Dougherty Week 2 Notes Chapter 3 - Kinematics in two or three dimensions Vectors and scalars – velocity is how fast and in what direction the particle is moving o Magnitude – vector quantity o Scalar quantities are specified by numbers and units Addition of vectors – graphical methods o above D = displacement vectors o above v = velocity vectors Resultant displacement – represented by the arrow above the Dr o This should be smaller than the sum of the first displacement of the vector and the second displacement of the vector o The sum of the two vectors is called the resultant o Create a triangle by connecting the head and the tail of the two