|MadSci Network: Physics|
Judy, this question has a couple more variables than you mention in your question. If you think about the two skiiers in free fall (like Galileo's experiment) they would fall straight down with the same acceleration and would land at the same time, ignoring wind resistance. Coming down a frictionless hill would be the same thing - just a component of gravitational force, depending on the angle of the hill, works on the skiiers, and the larger weight has a greater force so they both land at the same time. i.e. F= m1*m2*G/(r^2) = m1*a so a = m2*G/(r^2) m2 is the earth's mass, G is the universal gravitational constant, and r is the distance from the mass to the earth's center of mass. However, there's always some friction between the skis and the hill, and, friction is proportional to weight, so if the snow were not real fluffy and close to frictionless, the bigger skiier's weight would slow her down. Go carts in the snow? If the go carts were on a hill where the road is smooth, then the mass wouldn't matter if we can ignore friction. They'd arrive at the same time. If we can't ignore friction then the heavier cart comes in last. Hope this helps!
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