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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) $ /", * / - I 73 2. Derive the principle of work and energy for a single particle. ( 5 points) [kN] 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) . - / a " /' - . /f'x/&x,; - - rC 4 ,TG ry t7 fL. 0 -%1 F 5. Use the instadeneous ;centers of velocity to determine the horizontal velocity of 'B. (5 = T m d d= /r--~67'fld -taM 'TL - = ,Q( - T1. - - = Sb,.,4 --r- I s7:r -Qc v p w ? - - / 4o-?-f - IJ- 57'4 2 4 Lo-, t4 4 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) I & $%,,\ '\ 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) A?- 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)