1. Matlab Computer Experiments (Contd.) Vibes and Waves in Action University of Massachusetts Lowell April 03, 2009

2. OUTLINE Learn how to solve equations: Using Matlab commands : Syms : for representing variables Sym : for representing equation Solve : for solving for required variable Subs : for substituting numbers into the variables Examples: Learn how to code the equation : F = m*a. Review of Equations

3. Matlab Commands  syms var1 var2 …..  Short cut for representing variables.  X = sym(‘ Equation’ )  Represents the equation  g = solve(X, var)  Solution of equations.  subs(X,var1,value)  Substitutes value in equation X for var1.

4. Review Acceleration : Rate of change of velocity Newton’s second law: Force is equals to mass times acceleration

5. Review contd… v2,v1,t2,t1 Force : Given v2,v1,t2,t1 Momentum: Equals to mass times velocity

6. Problem  What is the momentum of a 50 kg carton that slides at 4 m/sec across an icy surface?  The sliding carton skids onto a rough surface and stops in 3 sec. Calculate the force of friction it encounters?