Man vs Iron Weight: Understanding Acceleration in UAH PDF

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The discussion centers on the difference in acceleration when a man pulls on a rope with a force of 600N compared to an iron weight of 60Kg attached to the same rope. When the system begins to move, the iron weight generates less acceleration due to the tension in the rope being less than the weight itself. As the weight falls, the tension must be lower than 600N, indicating that the force exerted by the man does not equal the weight of the hanging mass. This clarification highlights the relationship between force, tension, and acceleration in the system. Understanding these dynamics is crucial for grasping the principles of physics involved.
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http://www2.uah.es/jmc/ai14.pdf

On page 2 of the above pdf there is an example in a box with title 'Acceleration'
which states that there is a difference between a man pulling on a rope with 600N force and an iron weight of 60Kg (g = 10) tied to the rope. The difference being that once the system starts moving the iron weight generates less acceleration. I don't understand the explanation given. Could someone please explain in a different way.

Thanks,

E.
 
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What pulls the cart is the tension in the rope. Which case produces the greater tension? Hint: If the cart is accelerating, can the tension equal the weight of the hanging mass?
 
Emanresu said:
http://www2.uah.es/jmc/ai14.pdf

On page 2 of the above pdf there is an example in a box with title 'Acceleration'
which states that there is a difference between a man pulling on a rope with 600N force and an iron weight of 60Kg (g = 10) tied to the rope. The difference being that once the system starts moving the iron weight generates less acceleration. I don't understand the explanation given. Could someone please explain in a different way.

Thanks,

E.

The man keeps applying a force of 600 N.

Now consider the weight as it is falling. What is the tension in the rope? Since the weight is accelerating downward, the tension in the rope has to be less than the iron weight therefore the tension is less than 600 N.
 
Duh ! It seems so obvious now !

Thanks,

E.
 

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