The bob of a simple plane pendulum of mass $m_0$ and length $l_0$ is connected to two small blocks, one of mass $m_1$ by a dashpot, and the other of mass $m_2$ by a spring. The dashpot (with dashpot constant $c$) and spring (with spring constant $k$) are both ideal and massless. The spring is unstreched when the pendulum is vertical and the masses are at the positions shown. An external force $F(t)$ acts on $m_2$. Assume small motions such that the dashpot and the spring remain almost horizontal at all times. Note that gravity acts. i. How many degrees of freedom does the system have? Pick generalized coordinates and describe the generalized coordinates clearly. ii. Find the equation(s) of motion using Lagrangian approach.
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In this case, we can choose the position of the mass as one generalized coordinate, denoted by x. Since the spring remains almost horizontal at all times, we can assume that the vertical position of the mass is constant and does not affect the dynamics of the Show more…
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