Question

Mechanics of Machines IV

ASSIGNMENT 06 (SELF-ASSESSMENT QUESTIONS) If not given take g . 9.81 m/s. ESTEEL m 200 GPa and GSTEEL # 80 GPa EALUMINUM 70 GPa and GALUMINUM 26 GPa -126 GPa and GCOPPER ECOPPER 17 GPa NB: 1. There are two sections in this assignment. Attempt ALL questions from sections A and B 2 Multiple choice questions, (MCOs) may not necessarily be used in the examination and learners should not expect to find (MCQs) in examination papers SECTION A Consider the following case and use it to answer the questions in this section. CASE: A system of springs with effective stiffness of k # 29823 N/m and a damper of damping coefficient c 17 2 Ns/m support a mass m- 6.2 kg Question1 If the initial conditions xo = 0 4 and vo 4 m/s determine the expression for the displacement of the mass at any time, x(t). a)0.4cos6.936r +0.5968 sin6.936r (b) r() r"s"[04sin 6.936, +0.5068cos 6.936] (c) - o.5968 sin6.7951+0.4cos6.795 (d))o 5968 cos 6.795t+04sin6.795 Question 2 Determine the expression of the velocity, v(t), at any t (b) vo)se-ur,[-0556cos 6.79%-4. 111 sin 6.7951] (c) v)0.4084 cos6.936r-1.105sin 6.936 (d) o)e[27.13cos6.795t-5.82 sin 6.795 (e) 4.195sin6.9361-0.5504 cos6.936 Question 3 Determine the expression of the acceleration, vit), at any t (a) ae9.630sin6.936-28.33cos6.936r] (c)a)-7718cos6.795-176.26sin6.7951 (d) a(r)"c","T-25.66 sin 6.795,-13.02cos 6.795,] (e) a)e-27.16cos 6.795+9.481 sin6.795r Question 4 Determine the displacement after 0.01 seconds (a) x()-0.5899m- 589.9mm (b) x(r)-0.07932m-79.32mm (c) x(t)-0.080 14m=80.14mm (d) x(r)-0.30722m-307.22mm (e) x()-0.07482m- 74.82mm Question 5 Determine the velocity after 0.01 seconds (a) (0.01)-26.30m/s (b) (0.01)-0.8282m/s (c) v(0.01)-3.942m/s (d) v(0.01) -0.8224m/s (e) v(0.01)-3,862m/s Question6 Determine the velocity after 0.01 seconds (a) a(0.01)- -87.74m/s (b) a(0.01)-27.21ms (c) a(0.01) -26.09m/s (d) a(0.01)--14.53m/s (e) a(0.01)--14.95m/s

Answer 1

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