# Homework for Lab 15: Simple Harmonic Motion Name Date Section 15 10 -5 -15-10-5 0 5…

Homework for Lab 15: Simple Harmonic Motion Name Date Section 15 10 -5 -15-10-5 0 5 10 15 Displacement (em) Figure 15.6: Force vs displacement graph for a 0.75 kg cart on a horizontal spring. 1. Figure 15.6 shows the force exerted by the spring on a 0.75 kg cart, as a function of its displacement from equilibrium. Positive displacements (in cm) represent stretching of the spring; negative displacements represent compression. Find the spring constant. 2. The cart is moved 2.0 cm beyond the equilibrium point (the spring is stretched). 259 260 LAB 15. SIMPLE HARMONIC MOTION (a) What is the elastic potential energy stored in the spring? Does this energy depend on the mass of the cart? (b) If the cart is relensed from rest at the 2.0 em mark, what will its kinetic energy be when it first passes through the spring’s equilibrium position? (c) If the cart is released from rest at the 2.0 cm mark, what will its velocity be when it first passes through the spring’s equilibrium position? 3. The period for oscillation of the cart is given by Tketch a graph of the displacement of the spring as a function of time in Fig. 15.7, again assuming that the spring was stretched by 2.0 cm when the cart was released from rest. Make sure that you put appropriate numbers on the vertical and horizontal axes. Time (s) Figure 15.7: Simple harmonic motion of the cart.