three logs

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Smooth, identical logs are piled in a stake truck. The truck is forced off the highway and comes to rest on an even keel lengthwise but with the bed at an angle θ with the horizontal. As the truck is unloaded, the removal of the log shown dotted leaves the remaining three in a condition where they are just ready to slide, that is, if  θ were any smaller, the logs would fall down. Find θ.


Solutions (listed by author)

Michael A. Gottlieb (pdf, 65K)

Sukumar Chandra (pdf, 99K)

Maciej Jarocki (pdf, 103K)


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