MT-1620 al.2002 Where dt (derivative with respect to time Drawing the free body diagram for this configuration Figure 19.11 Free body diagram for spring-mass system F=0→F-k q-mg =0 →m+kq=F(l Basic spring-mass system(no damping) This is a 2nd order Ordinary Differential Equation in time When the Ordinary/Partial Differential Equation is in space, need Boundary Conditions. Now that the Differential Equation is in time, need initial Conditions Paul A Lagace @2001 Unit 19q MIT - 16.20 Fall, 2002 where: • d ( ) = dt (derivative with respect to time) Drawing the free body diagram for this configuration: Figure 19.11 Free body diagram for spring-mass system ∑ F = 0 ⇒ F − k q − m ˙˙ = 0 ⇒ m q˙˙ + k q = F() t Basic spring-mass system (no damping) This is a 2nd order Ordinary Differential Equation in time. When the Ordinary/Partial Differential Equation is in space, need Boundary Conditions. Now that the Differential Equation is in time, need Initial Conditions. Paul A. Lagace © 2001 Unit 19 - 11