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Solution Assignment

1. A Carte having a mass of 60 kg falls horizontally off the back of a truck which is travelling at 80km/hr. Determine the coefficient of kinetic friction between the road and the crate if the crate slides 45 m on the ground with in no tumbling along the road before coming to rest. Assume that the initial speed of the crate along the road is 80 km/hr.

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2

2. If the system is released from rest, determine the speeds of both masses after B has moved 1m. Neglect friction and the masses of the pulleys.

Alternative solution

3

4

3. At the given instant member AB has the angular motions shown. Determine the velocity and acceleration of the slider block C at this instant. (Use vector analysis)

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5

4. The wheel rolls without slipping such that at the instant shown it has an angular velocity . Determine the velocity of point B on the rod at this instant.

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6

5. For the mechanism shown in figure, link 2 rotates at constant angular velocity. Construct the velocity polygon and determine the acceleration D.

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