This simulation show 11 pendulums with different initial angle(from [u][i]minimum angle[/i][/u] to [u][i]minimum angle+angle range[/i][/u])

1. (equation for real pendulum)

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this mode is demonstrate real pendulum swings at different period T for different magnitude of angle ?.

well done!

i like the view of all pendulum all superposition together.[img]http://www.phy.ntnu.edu.tw/ntnujava/index.php?action=dlattach;topic=2010.0;attach=3645;image[/img]

[quote author=Fu-Kwun Hwang link=topic=2010.msg7572#msg7572 date=1291342118]

2. (equation for small angle approximation :assume )

For the second mode: the period and damping factor are the same for all pendulums. Do you know why?

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This is due to the small angle assumption say ? = 5 degree, the period T has to be the same for the all ? = 5 degree.

i don't understand the question on "damping factor are the same for all pendulums", if b = 0.5, it will be the same of all models of the pendulums because that is the way the model is made to obey this mathematical equation (equation for small angle approximation :assume ).

is my interpretation of the question correct?