1. You are standing at the very rear of a 6.0m long, 120kg raft that is at rest in a lake with its prow only .5m from the end of the pier. Your mass is 60kg. Neglect friction between the raft and the water. A) How far from the end of the pier is the center of mass of the you-raft system? B) You walk to the front of the raft and then stop. How far from the end of the pier is the center of mass now? C) When you are at the front of the raft, how far from the end of the pier are you?(adsbygoogle = window.adsbygoogle || []).push({});

2. xcm= (m2*d)/(m2+m1)

where m1 and m2 are mass one and mass two, xcm is center of mass, and d is the difference in position of the particles.

3.A) By defining the pier as the origin and then I find the following equation. xcm= 60kg(5.5m)/180kg= 1.833m from the pier B) 60kg(0)/180kg = 0 C) .5m

I thought I had A) and C) right, but B) makes me second guess myself. What did I miss here?

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# Homework Help: How far from the end of the pier are you?

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