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College of Engineering Home Assignment # 2 Department: Mechanical Engineering Subject: Dynamics of Machines (ME 243/221) Date: 20/03/2014 Date of submission: 02/04/2014 QN. 1 Find out the acceleration of slider B, angular acceleration of connecting rod (link AB) for the configuration given below. A The geometrical data are given below. O1A = 480mm, Connecting rod AB= 1600 mm, = 600 and The crank O1A is B rotating at a constant angular velocity Ф of 20 rad/seconds counter clockwise. O1 Draw the velocity and acceleration diagram with complete details like Figure 1: Problem of question 1 included angles, lengths etc. Hint. O1A sin= AB sin Ф QN. 2. Determine the acceleration of A4 on link 4 for the quick return mechanism given below. Link 2 rotates 10 rad/sec CW. Fixed link O2O4= 300mm, Driving link O2A = 100mm, = 510 and β = 180 . Also find out coriolis component of acceleration and angular acceleration of link 4. O2 2 4 QN3. Two shafts A and B are co-axial. A gear C (50 teeth) is rigidly β mounted on shaft A. A compound gear D-E gears with C and an internal gear G. D has 20 teeth and gears with C and E has 35 teeth and gears with an internal gear G. The gear G is fixed and is concentric with the shaft axis. The compound gear D-E is mounted O4 on a pin which projects from an arm keyed to the shaft B. Sketch the arrangement and find the number of teeth on internal gear G assuming that all gears have the same module. If the shaft A rotates at 110 r.p.m., find the speed of shaft B. Ans: NB= 50 rpm CCW