Hello,

I'm trying to create a model of pendulum motion in Matlab to fit the curve we measured in class, and it has some non-linear components (friction). It looks like the best fit is a sinusoid with an envelope given by a parabola (see attached file).

The equations of motion are given by:
ϕ¨(t)=−k2ϕ˙(t)−k3sin(ϕ(t))

How this equation can be changed so that the solution of it is a searched sinusoid?

Thank you.

Question

Hello,

I'm trying to create a model of pendulum motion in Matlab to fit the curve we measured in class, and it has some non-linear components (friction). It looks like the best fit is a sinusoid with an envelope given by a parabola (see attached file).

The equations of motion are given by:
ϕ¨(t)=−k2ϕ˙(t)−k3sin(ϕ(t))

How this equation can be changed so that the solution of it is a searched sinusoid?

Thank you.

abhisar · Answer

Hello @farah777 ! Welcome to OS Pls post it in physics section as they would be able to help u out better. I would also like to tell u that posting questions in irrelevant section is considered spamming according to CODE OF CONDUCT of OS http://openstudy.com/code-of-conduct Thnx and stay in touch with OS

anonymous · Answer

ok thank you for telling me