Force exerted by 2 supports on the plank

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To determine the forces exerted by two supports on a plank with a crate, the torque equation is applied. The user calculated approximately 66 N for the first support and over 400 N for the second, while the expected answers are 130 N and 60 N. The discrepancy suggests a potential oversight, possibly the mass of the plank not being included in the calculations. The weight of the crate is noted as 73.5 N, indicating that additional factors may need consideration. Clarifying the mass of the plank is essential for accurate force calculations.
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Homework Statement


Suppose a crate of mass 7.5 kg is placed on the plank in the figure below, at a distance of 3.9m from the left end. Find the forces exerted by the 2 supports on the plank.


Homework Equations



Torque=radius*force


The Attempt at a Solution


I've used the tourque equation to get an answer around 66 for the force of the first support (the farthest to the left). I'm getting an answer in the 400's for the second support. I know the answers are supposed to be 130 N and 60 N. So, do I need to be using a different equation?
 

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A 7.5kg mass only represents a weight of about 73.5N. So something's missing in your problem statement, perhaps the mass of the plank?
 

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