posted by Matt .
As part of a training program, an athlete runs while holding 8.00 weights in each hand. As he runs, the weights swing through a 30.0 arc in . His hands are 72 from his shoulder joint, and they are light enough that we can neglect their weight compared with that of the 8.00 weight he is carrying.
What force does the runner's hand exert on each weight at the bottom of the swing?
At the bottom of the swing, both the weight and the centripetal force M V^2/R must be supperted by the hand.
You need to provide the units of the "weights". Newtons or pounds (weight)? Slugs or kilograms (mass)?
To come up wth a velocity V at the bottom of the arm's swing, you need to know how often the arm swings, and how the maximum velocity is related to the average velocity. (It is probbaly about twice the average)
You have not provided enough information to answer the question.
I wonder if this problem was assigned by a qualfied college physics teacher.