## Friday, March 28, 2014

### EJSS ammeter angular coil damping model

EJSS ammeter angular coil damping model, an original model by lookang
 EJSS ammeter circular coil damping model with critical damping http://weelookang.blogspot.sg/2014/03/ejss-ammeter-angular-coil-damping-model.html author: lookang author of EJSS 5.0 Francisco Esquembre

 EJSS ammeter circular coil damping model with critical damping http://weelookang.blogspot.sg/2014/03/ejss-ammeter-angular-coil-damping-model.html author: lookang author of EJSS 5.0 Francisco Esquembre

 EJSS SHM model with resonance showing Amplitude vs frequency graphs, heavy damping (RED) frequency ratio for better x azes values https://dl.dropboxusercontent.com/u/44365627/lookangEJSworkspace/export/ejss_model_SHMresonance01/SHMresonance01_Simulation.html author: lookang author of EJSS 5.0 Francisco Esquembre

## No damping

 EJSS ammeter circular coil damping model with no damping http://weelookang.blogspot.sg/2014/03/ejss-ammeter-angular-coil-damping-model.html https://dl.dropboxusercontent.com/u/44365627/lookangEJSworkspace/export/ejss_model_SHMcoil/SHMcoil_Simulation.html source: https://dl.dropboxusercontent.com/u/44365627/lookangEJSworkspace/export/ejss_src_SHMcoil.zip author: lookang author of EJSS 5.0 Francisco Esquembre

## Very light damping

 EJSS ammeter circular coil damping model with very light damping http://weelookang.blogspot.sg/2014/03/ejss-ammeter-angular-coil-damping-model.html https://dl.dropboxusercontent.com/u/44365627/lookangEJSworkspace/export/ejss_model_SHMcoil/SHMcoil_Simulation.html source: https://dl.dropboxusercontent.com/u/44365627/lookangEJSworkspace/export/ejss_src_SHMcoil.zip author: lookang author of EJSS 5.0 Francisco Esquembre

## Light damping

 EJSS ammeter circular coil damping model with light damping http://weelookang.blogspot.sg/2014/03/ejss-ammeter-angular-coil-damping-model.html https://dl.dropboxusercontent.com/u/44365627/lookangEJSworkspace/export/ejss_model_SHMcoil/SHMcoil_Simulation.html source: https://dl.dropboxusercontent.com/u/44365627/lookangEJSworkspace/export/ejss_src_SHMcoil.zip author: lookang author of EJSS 5.0 Francisco Esquembre

## Moderate damping

 EJSS ammeter circular coil damping model with moderate damping http://weelookang.blogspot.sg/2014/03/ejss-ammeter-angular-coil-damping-model.html https://dl.dropboxusercontent.com/u/44365627/lookangEJSworkspace/export/ejss_model_SHMcoil/SHMcoil_Simulation.html source: https://dl.dropboxusercontent.com/u/44365627/lookangEJSworkspace/export/ejss_src_SHMcoil.zip author: lookang author of EJSS 5.0 Francisco Esquembre

## Critical damping

 EJSS ammeter circular coil damping model with critical damping http://weelookang.blogspot.sg/2014/03/ejss-ammeter-angular-coil-damping-model.html https://dl.dropboxusercontent.com/u/44365627/lookangEJSworkspace/export/ejss_model_SHMcoil/SHMcoil_Simulation.html source: https://dl.dropboxusercontent.com/u/44365627/lookangEJSworkspace/export/ejss_src_SHMcoil.zip author: lookang author of EJSS 5.0 Francisco Esquembre

## Heavy damping

 EJSS ammeter circular coil damping model with heavy damping http://weelookang.blogspot.sg/2014/03/ejss-ammeter-angular-coil-damping-model.html https://dl.dropboxusercontent.com/u/44365627/lookangEJSworkspace/export/ejss_model_SHMcoil/SHMcoil_Simulation.html source: https://dl.dropboxusercontent.com/u/44365627/lookangEJSworkspace/export/ejss_src_SHMcoil.zip author: lookang author of EJSS 5.0 Francisco Esquembre

## YJC note

 2) Moving-coil meters Critical damping is an important feature of moving-coil meters which are used to measure current and voltage. When the reading changes, it is of little use if the pointer oscillates for a while or takes too long to settle down to the new reading. The new reading must be taken quickly in case it changes again. Thus, a pointer is critically damped to allow it to move to the correct position immediately whenever a current flows through it or a voltage is applied across it.

## The equations that model the motion of the car suspension spring mass system are:

Mathematically, the restoring force $F$ is given by

$F = - k (\theta - \theta_{0})$

where $F$  is the restoring elastic force exerted by the spring (in SI units: N), k is the spring constant (N·m−1), and $\theta$ is the displacement from the equilibrium position $\theta_{0}$ (in radians).

Thus, this model assumes the following ordinary differential equations:

$\frac{\delta \theta }{\delta t} = \omega$

$\frac{\delta \omega }{\delta t} = -\frac{k}{m} (\theta - \theta_{0}) - b\frac{\omega}{m} +$

where the terms

$-\frac{k}{m} (\theta - \theta_{0})$ represents the restoring force component as a result of the coil spring extending and compressing.

$- b\frac{\omega}{m}$ represents the damping force component as a result of dampers retarding the car mass's motion.