In tearing a paper towel or plastic bag

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A sharp jerk when tearing a paper towel or plastic bag is more effective due to the greater acceleration produced, which generates a higher force, facilitating the tear. The discussion highlights that the roll's ability to rotate plays a role in this process, as it allows one piece to accelerate while the rest remain stationary. The concept of inertia is also relevant, as the sudden change in motion causes the material to tear at the perforated edges. The mechanics of tearing involve both force and the dynamics of motion, similar to how passengers react in a moving bus. Understanding these principles clarifies why a quick pull is more successful than a slow one.
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1. In tearing a paper towel or plastic bag from a roll, why is a sharp jerk more effective than a slow pull



2. I found this answer online

A quick, sharp jerk means a greater acceleration and a greater acceleration means a greater force. And it is force that tears the paper towel or plastic bag


The Attempt at a Solution



I was thinking not only the force of the jerk like the answer online said but wouldn't it be as well because the roll is ƩF = 0 and the quick acceleration of the one piece while the rest remain unmoved?

I don't know if that is confusing sorry if it is.
 
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Is the roll free to rotate?

If so ask yourself why the paper would ever tear?
 
CWatters said:
Is the roll free to rotate?

If so ask yourself why the paper would ever tear?

I am making an assumption saying it is free to rotate, every single one I have encountered is. usually it tears because of the perforated edges. As well as I am assuming that the force and the jerk kind of the theory of the bus - when the bus accelerates you move forward and when it decelerates you move backward. the paper towel that you grabbed in my mind has the same theory its moving at a constant rate with a sudden change.
 
I think the word you are looking for is "Inertia".
 

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