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Mechanics Force Question A level

Quick mechanics question (a level).

Please try to picture this diagram: there is a uniform rod being suspended horizontally by two strings either side which hang the rod from the ceiling. If an object is on this rod, is it true that you do not consider the to be a Reaction force between the rod and the object because you consider it in the tension of the strings?
Reply 1
Original post by Maria303
Quick mechanics question (a level).
Please try to picture this diagram: there is a uniform rod being suspended horizontally by two strings either side which hang the rod from the ceiling. If an object is on this rod, is it true that you do not consider the to be a Reaction force between the rod and the object because you consider it in the tension of the strings?

If youre talking about the rod being in equilibrium, then you only consider the forces acting on the rod so

string tensions at each end

weight of the rod (gravity is a non contact force)

weight of the object acting on the rod


The reaction force between the rod and object acts on the object, not the rod.
Reply 2
Original post by mqb2766
If youre talking about the rod being in equilibrium, then you only consider the forces acting on the rod so

string tensions at each end

weight of the rod (gravity is a non contact force)

weight of the object acting on the rod


The reaction force between the rod and object acts on the object, not the rod.

Thank you so much - that makes sense !

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