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INDIVIDUAL ASSIGNMENT 2 (BDA 20103) SEMESTER 2 2013/2014 INSTRUCTIONS: 1) Please answer ALL questions. 2) Submit the answers no later than MONDAY, 14 APRIL 2014 (4:00pm) to D1-209 to avoid any penalty. GOOD LUCK!

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Question 1: Determine the acceleration of block A (mass 20 kg) when the system is released. The surface upon which block B (mass 10 kg) is rests is smooth. Neglect the mass of the pulleys and cords.

Question 2: A toboggan and rider have a total mass of 100 kg and travel down along the (smooth) slope defined by equation y = 0.2 x2. At the instant x = 8 m, the toboggan’s speed is 4 m/s. At this point, determine the rate of increase in speed and the normal force which the toboggan exerts on the slope. Neglect the size of the toboggan and rider for the calculation.

Question 3: The 2 kg cylinder os moving on the circular path due to the rotation of the forked rod. If the rod maintains a constant angular motion of 0.5 rad/s, determine the force which the rod exerts on o the cylinder at the instant 30 . Neglect the effect of friction in the calculation.

Question 4: A car having a mass of 2 Mg strikes a smooth rigid sign post with an initial speed of 30 km/h. To stop the car, the front end horizontally deforms 0.2 m. If the car is free to roll during the collision, determine the average horizontal force causing the deformation.

Question 5: A motor hoists a 50 kg crate at constant speed to a height of h = 6 m in 3 s. if the indicated power of the motor is 4 kW, determine the motor’s efficiency.

Question 6: A hockey puck is traveling to the left with a velocity of v 1 = 10 m/s, when it is struck by a hockey stick and given a velocity of v 2 = 20 m/s as shown. Determine the magnitude of the net impulse exerted by the hockey stick on the puck. The puck has a mass of 0.2 kg. The angle between v 1 and v 2 is 40o.

Question 7: A 0.6 kg brick is thrown into a 25 kg wagon which is initially at rest. If, upon entering, the brick has a velocity of 10 m/s as shown, determine the final velocity of the brick and wagon.

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