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## Easy Java Simulations (2001- ) => Electromagnetism => Topic started by: Fu-Kwun Hwang on October 11, 2009, 05:20:56 pm

 Title: Similarity between RLC circuit and spring with damping Post by: Fu-Kwun Hwang on October 11, 2009, 05:20:56 pm A mass m attached to a vertical spring (spring constant k) in gravity field:The above system can be described with$F=m a_y= mg -ky -b v_y$ or $m\frac{d^2y}{dt^2}+b\frac{dy}{dt}+ky=mg$For a RLC circuit with DC source Vc:The above system can be described with$Vc=V_L+V_R+V_C$ or $L \frac{d^2Q}{dt^2}+I\frac{dQ}{dt}+\frac{Q}{C}=Vc$,  where $I=\frac{dQ}{dt}, V_R=I R, V_C=Q/C , V_L=L\frac{dI}{dt}$The differential equation are the same for the above two systems.So a damped spring system can be simulated with RLC circuit (or RLC circuit can be simulated with damped spring system,too!).