School of Science and Engineering Al Akhawayn University
Final Test
Egr3402, Fall 2004
Instructor: Dr. H. Darhmaoui Date: December 15, 2004
Name: …………………………… Duration: 110 min.
Problem 1:
The position of the L-shaped rod shown is controlled by a cable attached at B. Knowing that the rod supports a load of magnitude P = 50 lb, (a) calculate the tension T in the cable to maintain the rod in equilibrium at an angle = 70° , (b) what is the corresponding reaction at A.
School of Science and Engineering Al Akhawayn University
Problem 2:
A collar B, of weight W, is attached to the spring and may move along the rod shown. The constant of the spring is 15lb/in and the spring is unstretched when = 0. Knowing that the coefficient static friction between the collar and the rod is 0.40, determine the range values of W for which equilibrium is maintained when = 20°
School of Science and Engineering Al Akhawayn University
Problem 3:
A space vehicle is in a circular orbit of 2200-km radius around the moon. To transfer it to a smaller circular orbit of 2080-km radius, the vehicle is first placed on an elliptic path AB by reducing its speed by 26.3 m/s as it passes through A. Knowing that the mass of the moon is 73.49 x 1021 kg, determine (a) the initial speed of the vehicle in its circular orbit, (b) its speed as it approaches B on the elliptic path, (c) the amount by which its speed should be reduced as it approaches B to insert it into the smaller circular orbit.
(G = 6.673 x 10-11 m3/kg.s2)
School of Science and Engineering Al Akhawayn University
Problem 4:
Three identical freight cars have the velocities indicated. Assuming that car B is first hit by car A, determine the velocity of each car after all the collisions have taken place if (a) all three cars get automatically coupled, (b) cars A and B get automatically coupled while cars B and C bounce off each other with a coefficient of restitution e = 1 (i.e., without any loss of energy).
School of Science and Engineering Al Akhawayn University
Problem 5:
The assembly shown consists of two rods and a rectangular plate BCDE which are welded together. The assembly rotates about the axis AB with an angular velocity of 7.5 rad/s that decreases at the rate of 30 rad/s2. Knowing that the rotation is counterclockwise as viewed from B, determine the velocity and acceleration of corner C.
School of Science and Engineering Al Akhawayn University
Problem 6:
A l.2-lb collar can slide without friction along the semicircle rod BCD. The spring is of constant k = 1.8 lb/in and its unstretched length is 8 in. Knowing that the collar is released from rest at B, determine (a) the speed of the collar as it passes through C, (b) the force exerted by the rod collar at C.
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