- HW-1: Research stick-slip vibration phenomenon and prepare a short report. - HW-2: A spring-mass system with a mass of \( 3500 \mathrm{~kg} \) and stiffness \( 85,000 \mathrm{~N} / \mathrm{m} \) is subject to an initial displacement of \( x 0=7.5 \mathrm{~cm} \) and an initial velocity of \( x 0=10 \mathrm{~cm} / \mathrm{s} \). Plot the time variations of the mass's displacement, velocity, and acceleration using MATLAB. - HW-3: Wtih use the system parameters and initial conditions given in HW-2, plot the time variations of the mass's displacement, velocity, and acceleration using MATLAB for three different viscous damping constant, \( c=100 \mathrm{~N} . \mathrm{m} / \mathrm{s}, c=500 \mathrm{~N} . \mathrm{m} / \mathrm{s} \) and \( c=1000 \mathrm{~N} . \mathrm{m} / \mathrm{s} \)