Tension in string when force is applied to both ends

AI Thread Summary
When a force is applied to both ends of a string, the total tension is not the sum of those forces; they do not cancel each other out. For instance, to achieve a tension of 100 N in a massless string, a force of 100 N must be applied at each end. In a vertical string with a mass hanging from it, the downward force exerted by the mass is equal to the upward force from the attachment point. This creates equilibrium, demonstrating that the forces are equal but do not combine to increase tension. Understanding this principle is crucial for analyzing tension in strings under load.
vaizard
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Hi,

I've got a quick question about tension. If there is a force applied to both ends, the total tension is the sum of those forces, right (i.e., they don't cancel each other out)?

TIA!
 
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Wrong. Take a massless string for example. To create a tension of 100 N within the string, you must apply a force of 100 N to both ends. (Those forces don't add up.)
 
So when the string is vertical and in equilibrium with a mass hanging from it, there is a certain force exerted downwards by the mass and that same force exerted upwards by whatever the top end of the string is attached to?
 
That's right.
 

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