  This paper reports a computer model- simulation created using Easy Java
Simulation (EJS) for learners to visualize how the steady-state amplitude of a
driven oscillating system varies with the frequency of the periodic driving
force. The simulation shows (N=100) identical spring-mass systems being
subjected to (1) periodic driving force of equal amplitude but different
driving frequencies and (2) different amount of damping. The simulation aims to
create a visually intuitive way of understanding how the series of amplitude
versus driving frequency graphs are obtained by showing how the displacement of
the system changes over time as it transits from the transient to the steady
state.
  A suggested how to use the model is added to help educators and students in
their teaching and learning, where we explained the theoretical steady state
equation, time conditions when the model starts allowing data recording of
maximum amplitudes to closely match the theoretical equation and steps to
collect different runs of degree of damping. We also discuss two design
features in our computer model: A) displaying the instantaneous oscillation
together with the achieved steady state amplitudes and B) explicit world view
overlay with scientific representation with different degrees of damping runs.
  Three advantages of using EJS include 1) Open Source Codes and Creative
Commons Attribution Licenses for scaling up of interactively engaging
educational practices 2) models made can run on almost any device including
Android and iOS and 3) allows for redefining physics educational practices
through computer modeling. 2015 resource:
http://iwant2study.org/ospsg/index.php/interactive-resources/physics/02-newtonian-mechanics/09-oscillations/88-shm24
