Static equilibrium conditions are applied to the case of moving a piece of furniture. Assume that two people are carrying a piece of furniture down a hill with a uniform speed. The load distribution on both people is found to be a function of the slope of the hill, the difference in the heights of the two people, the length of the furniture, and, more importantly, the force angle that the person at the upper end applied relative to a horizontal line. Some interesting features are revealed through this analysis. For example, contradictory to our common sense, the person at the lower end does not always carry more ‘‘weight.’’ This problem was found to be effective in helping students develop the static equilibrium concept.

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