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The Grinch Goes Up Mount Crumpit

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The Grinch Goes Up Mount Crumpit

Down in Who-ville, no one knows that all their Christmas trees, presents, decorations and roast beasts have been stolen. Max, on the other hand, is perfectly aware of this. Not just because it all landed on him as he stood next to each home, but also because he now has the impossible job of dragging the entire sleighful of hot Christmas items back up the mountain.

We'll make the following assumptions: in each home the Grinch stole one Christmas tree (average weight: 50 pounds), one roast beast (25 pounds average), 20 Christmas gifts (average weight: 5 pounds), miscellaneous ornaments, food items, etc, weighing in at another 100 pounds. We'll also assume that the Grinch burgled 40 houses. The weight of the Grinch's sleigh is 550 pounds, and the Grinch himself is 300 pounds.

Finally, the angle of inclination of Mount Crumpit is a whopping 60ยบ, and the coefficient of static friction between the sleigh and the snow is 0.1. How much force will it take to get that sleigh started up the mountain?

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Problem by Mr. Twitchell


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