부산대학교 도서관

I would like to offer an alternative solution to the September 2022 Challenge "Second to one."[1] It is mathematically simpler, shorter, and makes it easy to see why the final expression for I t i turns out to be independent of I i . Additionally, I v i SB I x i sb SP 2 sp + I v i SB I y i sb SP 2 sp = I v i ' SB I x i sb SP 2 sp + I v i ' SB I y i sb SP 2 sp , since the speeds of the two rocks are the same. In the last equation, it is taken into account that after 1 s, the initial velocity of the second rock in the free-falling system is increased in the I y i direction by I v i SB 0 sb = I g i (1), and the same refers to the point P. Also, the initial positions of the rock and the spot P are shifted by (1/2) I g i (1) SP 2 sp in the I y i direction. [Extracted from the article]