The turning effect, what is actually physically happening that causes it?

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When lifting an object with a long stick, more force is required due to the increased torque created by the lever effect, not because the object's true mass changes. The concept of 'relative mass' arises from the moment of inertia, which describes how difficult it is to lift the object based on the distance from the pivot point. The vertical force needed to lift the mass remains constant, but the torque increases with longer levers, making the lift feel heavier. In rotational scenarios, such as a weight on a spinning arm, the larger circumference of a longer arm results in greater acceleration, affecting the force experienced. Ultimately, the perceived increase in effort is due to the mechanics of torque and moment of inertia rather than an actual increase in mass.
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Ok, so if an obect is picked up by holding it at the end of a 5 metre stick, then the object requires more force to lift, than at the end of a 1 metre stick, or with no stick at all.

1)Now I understand the Effect of this, What I don't understand is why this happens?
The true mass of the object remains the same, but to me trying to lift it on a long stick it has a 'relative mass' which is far greater than its true mass.
For the purposes of me lifting it, the object has gained a 'relative mass'.
How can this be possible? What is physically taking place that causes this?
It sound a lot like getting something for nothing, and that's why I'm confused.

2)Does this 'relative mass' work for centrifugal force aswell?
If a 10kg weight upon the end of a fixed arm 5 metres long were to spin at 1 rotation per second, how much force does the 10 kg weight contain, compared to the same apparatus but with a 3 metre arm?
Is the difference in force, all explained by the larger circumference (thus greater acceleration)that the 5m arm must travel in the 1 second?
Or would turning effect play apart aswell?
As ever, a bit long winded, but i would really appreciate some feedback, thankyou.
 
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Pyro Ninja said:
Ok, so if an obect is picked up by holding it at the end of a 5 metre stick, then the object requires more force to lift, than at the end of a 1 metre stick, or with no stick at all.
With a long stick only the contact forces at different areas of your hand are greater, but they are opposing each other, so the net vertical force exerted by the hand on the stick is the same. The stick acts as a lever and creates a large torque, while your hand has the shorter end:
http://en.wikipedia.org/wiki/Lever
 
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You have to do the same amount of work no matter how you lift it (ideally). You can either do that work quickly or take your time. Doing it quickly will tire you out more (it takes more force).

Think about hiking up a mountain... You could bee line straight up to the top but that takes more force and tires you out. What you do instead is take your time and snake around the mountain.
 
This is an example of a point mass Moment of inertia. This describes your 'relative mass'.

The vertical force required to lift the mass remains the same, the torque applied due to the increased moment is what makes it more difficult to lift.Also to answer your second question this does affect rotation. Think of an ice skater spinning round, when they pull their arms in they spin faster.
 
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In the first case you will have to apply an extra moment equal to that created by the mass acting along the length of the stick inorder to lift the mass. It is this moment created by the mass that gives you the feel of an extra load or effort in lifting.
Simply applying a weight equal to the hanging mass, at thelifting end won't help.

For thr second case , Chris has done all the expalining right by the example.
 
I think it's easist first to watch a short vidio clip I find these videos very relaxing to watch .. I got to thinking is this being done in the most efficient way? The sand has to be suspended in the water to move it to the outlet ... The faster the water , the more turbulance and the sand stays suspended, so it seems to me the rule of thumb is the hose be aimed towards the outlet at all times .. Many times the workers hit the sand directly which will greatly reduce the water...

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