how can we find damping constant from graph of amplitude versus time?
Hi sri sayye! http://img96.imageshack.us/img96/5725/red5e5etimes5e5e45e5e25.gif [Broken]
You'll need to look for the formula in your textbook or using Google, but it involves the ratio of successive peaks in that oscillatory response to a step input.
You might even find it in a previous thread on this topic at the foot ⇓ of this page
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