Solving a Lever System: Lever Arm and Load Lengths

AI Thread Summary
The discussion centers on calculating the effects of a load acting as a lever in a lever system. The user has a 3 lb load with its center of mass at 32 inches, attached to a lever with a 1-inch arm and a 14-inch arm. They seek to understand if the total effective length of the lever arm becomes 46 inches when the load is attached, and if this means they need 46 times the force on the opposite side to lift the load. The consensus is that the center of mass of the load should be considered to determine its impact on the lever system. Understanding these principles is crucial for accurately designing the lever mechanism.
Cloud9TN
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Forgive me if this is in the wrong category.

I have a product I am working out - I am a programmer and electronic engineer by trade, which didn't include a lot of work with physics principles.

I have a lever system which seems simple - but the trick is, my load is acting as a lever too. See the attached picture.

In the bottom left is my load. It is 3 lbs. I want to attach it to the end of the lever in the bottom right. My assumption has been that I would find the center mass of my load to determine how much longer my lever arm becomes with the load attached.

At the top of the picture, I sketch my 'assumed' equivalent system. I am right?

If so, is it correct that I need 46x the force on the left side of the lever to raise my 3lbs => 138lbs

Thanks in advance for the brainpower!
 

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I would like to clarify my description a little:

The load is 3lbs - the load center mass is at 32"
The unloaded lever system has a 1" arm and 14" arm on each side of the fulcrum.
The load gets attached to the end of the 14" arm (extending it)

I assume 14" (arm) + 32" (center mass) = 46" with 3lb load is the result.
 
jedi,

that doesn't help because my issue is understanding how the length of my load affects the equivalent system.

I suppose the ultimate question is - do I take the center of mass of my load to determine where on the lever system it is applied?
 
Last edited:
Yes, I think you take the center of mass of your load and its distance from the axis of the arm.
 
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