= 4. A pin is constrained to move in a guide slot whose curve is defined by y -x+x, as shown in Fig. 1.60. The pin is being pushed by a motor such that it Figure 1.60 78 CHAPTER 1 BASIC PRINCIPLES y(x) = x + x X === = 0, x(0) = 0.5 s, and find has an acceleration x(t) 1 +0.2t. The initial conditions are at t 0.6, x(0) = 0. Find the acceleration of the particle when t the radius of curvature at that instant. =