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.
again the
model can be used to understand the effects of increasing levels
of damping.
the picture
shows no damping case b = 0
the picture shows light damping case b =
0.1
the picture shows critically damping
case b = 2.0
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 picture
shows heavy damping case b = 5.0
Model:
http://dl.dropboxusercontent.com/u/44365627/lookangEJSworkspace/export/ejss_model_SHM22/SHM22_Simulation.xhtml