# - I Oct WEL ```EM311M - Dynamics
Exam 2
Monday, Oct 29, 2007, 6:00 - 8:00 p.m., WEL 136
1. The ball of mass m is suspended by cables A and B. Cable B is cut. Is the force in cable
n 7A going to increase or decrease ? Explain ( 5 points) \$
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2. Derive the principle of work and energy for a single particle. ( 5 points)
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3. Use the definition of work to compute the work of a constant force F = (-1,3)
along the segment AB of a straight line with A(1, I), B(2,2). (5 points)
4. Derive the principle of angular impulse and momentum for a single particle. (5 points)
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6. The 10-kg mass m rotates around the vertical pole in a horizontal circular path of radius
R = lm. For what range of values of the velocity v of the mass will the mass remain in the
circular path decsribed? (25 points)
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7. A ball is given a horizontal velocity of 3 m/s at 2m above the floor. Determine the
distance D between the ball's first and second bounces if the coefficient of restitution is
e = 0.6. (25 points)
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8. Bar A B has an angular velocity of 4 rad/s in the clockwise direction and an angular
acceleration of 10 rad/s2 in the counterclockwise direction. What is the acceleration of pin
B relative to the slot ? (25 points)
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