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2.4: Examples

  • Page ID
    91458
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    Here are examples from Chapter 2 to help you understand these concepts better. These were taken from the real world and supplied by FSDE students in Summer 2021. If you’d like to submit your own examples, please send them to the author eosgood@upei.ca.

    No examples submitted from students, yet. In the mean time, here are examples from Engineering Mechanics, Jacob Moore, et al.

    Example \(\PageIndex{1}\)

    The diagramA 3-pound box (A) rests on top of a 5-pound box (B), which rests on top of a flat surface. below shows a 3-lb box (Box A) sitting on top of a 5-lb box (box B). Determine the magnitude and direction of all the forces acting on box B.

    Figure \(\PageIndex{2}\): problem diagram for Example \(\PageIndex{1}\); two stacked boxes sitting on a flat surface.
    Solution
    Video \(\PageIndex{2}\): Worked solution to example problem \(\PageIndex{1}\), provided by Dr. Jacob Moore. YouTube source: https://youtu.be/J54OZSitzzM.
    Example \(\PageIndex{5}\)

    Barrels A and B are supported in a foot truck as seen below. Assuming the barrels are in equilibrium, determine all forces acting on barrel B.

    A 150-lb barrel (A) is stacked on top of a 200-lb barrel (B), with both placed on a handcart. The cart is tilted so the bottom is 30 degrees above the horizontal.
    Figure \(\PageIndex{6}\): problem diagram for Example \(\PageIndex{5}\); two barrels stacked on their sides are on a handcart, whose bottom is tilted upwards.
    Solution
    Video \(\PageIndex{6}\): Worked solution to example problem \(\PageIndex{5}\), provided by Dr. Jacob Moore. YouTube source: https://youtu.be/8DgrClhT4AM.
    Example \(\PageIndex{8}\)

    A hot air balloon is tethered to the ground with three cables as shown below. If the balloon is pulling upwards with a force of 900 lbs, what is the tension in each of the three cables?

    A hovering hot-air balloon, attached to the ground by 3 cables, is shown on a 3-dimensional coordinate plane. The balloon is 30 ft above the origin, cable A is attached to the ground 20 ft to the left of the origin, cable B is attached to the ground 30 feet to the right of and 20 feet in front of the origin, and cable C is attached to the ground 20 ft behind the origin.
    Figure \(\PageIndex{9}\): problem diagram for Example \(\PageIndex{8}\); a hot-air balloon is tethered to the ground by 3 cables, whose points of contact with the ground are given in relation to a three-dimensional coordinate plane. Adapted from image by L. Aragon CC-BY-SA 3.0.
    Solution
    Video \(\PageIndex{9}\): Worked solution to example problem \(\PageIndex{8}\), provided by Dr. Jacob Moore. YouTube source: https://youtu.be/HQqNGJR3ybQ.

    2.4: Examples is shared under a CC BY-NC-SA 4.0 license and was authored, remixed, and/or curated by LibreTexts.

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