Computational Physics - Department of Physics

8.7 Physics Project: the pendulum 267

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Fig. 8.10Plot ofθas function of timeτwithQ= 2 ,ωˆ= 2 / 3 andAˆ= 1. 35. The mass of the pendulum is set
equal to 1 kg and its length to 1 m. The inital velocity isvˆ 0 = 0 andθ 0 = 0. 3. Every timeθpasses the value±π
we reset its value to swing betweenθ∈[−π,pi]. This gives the vertical jumps in amplitude.

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Fig. 8.11Phase-space curve after 10 periods withQ= 2 ,ωˆ= 2 / 3 andAˆ= 1. 35. The mass of the pendulum is
set equal to 1 kg and its lengthl= 1 m. The inital velocity isvˆ 0 = 0 andθ 0 = 0. 3.