# One Fisherman: center of mass

1. Mar 2, 2009

### mrnastytime

1. The problem statement, all variables and given/known data
A man decides to boat out on the lake for a relaxing day of fishing. At one point during the day, he finds himself facing the shore. He judges that he is a distance Dinit = 35 ft from the shore. The man has a mass of Mman = 190 lbs, and the boat a mass of Mboat = 270 lbs. The boat has two seats each located a distance x = 5 ft from the center of the boat.

2. Relevant equations
Where is the center-of-mass of the man-boat system relative to the shore?
Deciding that more fish are to be found closer to shore, the man switches to the other seat. Assume there is no friction between the boat and the water. After switching seats, the man realizes that the boat has moved farther from the shore.

What is the new distance between the man and the shore after he switched seats?

3. The attempt at a solution
Xcm=X1*M1+X2*M2/(M1+M2)
Xcm=35*190+(35-5)*270/(190+270)
This is not the correct answer. What equation am i suppose to use?

Last edited: Mar 2, 2009
2. Mar 2, 2009

### mrnastytime

nevermind i figured it out