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# Physics moments question watch

1. A non-uniform rod JK of length 2m and weight 30N is placed on a support at L , where JL is 50cm. The road has a particle of weight 20N attached to end J. It is in equibrium, find distance from j to the centre of mass of rod
2. (Original post by Hasham123)
A non-uniform rod JK of length 2m and weight 30N is placed on a support at L , where JL is 50cm. The road has a particle of weight 20N attached to end J. It is in equibrium, find distance from j to the centre of mass of rod
Draw a diagram of the forces acting on the rod. You know where they are, with the exception of the weight of the rod, so pick any point to the right of L for the centre of gravity of the rod, call this point M, and call the distance JM d. You should now be able to solve this like a normal moments problem, so long as you choose the point to take moments about carefully.

Can you see why the centre of mass must be to the right of L? (And when I say "to the right", I am assuming a diagram of the rod that has J on the left and K on the right.)
3. I figured it out but thank you for replying

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Updated: October 21, 2017
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