Pulley & Angle: Tension Calculation

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Calculating the tension in a wire wrapped around a pulley involves understanding the impact of angles on force distribution. When pulling with a force of 50 kN, the tension can be affected by the angle at which the wire bends. The tension in the wire increases as the angle increases, contrary to the initial assumption that it decreases. A common approach is to decompose the tension into components parallel and perpendicular to the direction of the pull. Clarifying calculations and sharing detailed work can help identify any misunderstandings in the tension dynamics.
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Hello everybody

Im trying to calculate the tension in wire (se attached image). the wire is wrapped around a pulley and combined in the end at which you pull with 50 kN. As far as I understand, if youdon´t have this angle so that that the wire ends follow the red dotted line then one can just divide the pulling strength by a factor of 2. But how does this angle influence?

Best regards
 

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decompose the tension force on the string into two components. One of the components ought to be parallel to the red line while the other component will be perpendicular
 
dauto said:
decompose the tension force on the string into two components. One of the components ought to be parallel to the red line while the other component will be perpendicular

If the wire is bend a certain angle A, then the tension in the wire would be F*cos(A)?, then this would make the tension in the wire smaller - I have done this experiment in real life and experienced a smaller force was nessecary in order to brake the wire compared to a normal pull in the wire.
Am I not understanding you rigth?
 
RorschachDK said:
If the wire is bend a certain angle A, then the tension in the wire would be F*cos(A)?, then this would make the tension in the wire smaller - I have done this experiment in real life and experienced a smaller force was nessecary in order to brake the wire compared to a normal pull in the wire.
Am I not understanding you rigth?

It's the other way around - the tension in the wire is greater not smaller when there's an angle. You may have multiplied somewhere when you should have divided? Show your work and someone here will spot the problem.
 
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