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Subject: Solving 2nd order ode in Simulink
Date: Tue, 30 Dec 2008 19:03:03 +0000 (UTC)
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Hello,

It looks like if one cascades two integrators, he does not get a 2nd order ode solved.

For example, my 2n order ode is:

y'' + gy = Msin(wt). 

g is a constant. 

The solution to this ode shd be a sine function. When I cascade two integrators, I do not see a sine function resulting in simulink. Why?

I also noticed that if one used a sine block (Msinwt) as input to an integrator, he gets the output of the integrator as M+Mcos(wt). Why not just Mcos(wt)?

Can someone provide a solution to these?

ES