Exam Text n3 1

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Exam of APPLIED MECHANICS Study Track in Chemical Engineering September 06, 2016 Exercise n.1 This exercise must be solved only by students who ha ve failed the Intermediate Test or previous exams, or by students who want to improve the mark they got with the Intermediate Test or exams. Students who want to improve their mark about kinematics must only solve the part of kinematics of the exercise n.1. Students who want to improve their mark about dynamics must only solve the part of dynamics of the exercise n.1, by assuming that all the kinematic parameters that are necessary to be defined, in order to solve the problem, are known (in this case, please, draw arbitrary but likely direction and versus of these kinematic parameters). The mechanical system illustrated in Fig. 1 can move in a vertical plane. The bar HO, hinged to ground at point O, has a barycentre G 1, a mass m1 and a mass moment of inertia JO, evaluated about an axis passing through point O. A slider, having a barycentre C and a mass m3 can move on the inclined plane AB . This slider is connected to the bar HO by means of the bar CD, whose mass is negligible. A rigid body, having a barycentre G2, a mass m2 and a mass moment of inertia JG2, is supported on the bar HO. It is assumed that no slippage occurs between this body and the bar HO, owing to the static friction coefficient fs. The kinetic friction coefficient between the slider and the inclined plane is fk. At the given time the slider is moving with velocity v and acceleration a (see Fig. 1) under the effect of the unknown drive force Fd. All the geometrical parameters are assumed to be known (the thickness of the bar HO and the slider are negligible). You are asked to describe the procedure to: 1 evaluate the angular velocity and angular…