Does a massless string cause a normal force when attached to a wall?

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SUMMARY

The discussion centers on the mechanics of a massless ideal string and its interaction with a wall when tension is applied. It is established that while a massless string does not exert a normal force on the wall, the tension in the string can create a normal component at the point of attachment. This normal force arises not from the string itself but from the weight of the object (e.g., a ball) hanging from the string. If the hanging weight is removed, the string becomes limp and exerts no force, confirming that the normal force is contingent on the presence of the weight.

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  • Understanding of Newton's laws of motion
  • Familiarity with tension forces in physics
  • Knowledge of normal force concepts
  • Basic principles of static equilibrium
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Students of physics, educators teaching mechanics, and anyone interested in understanding the dynamics of forces and tension in systems involving strings and attachments.

laser
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Homework Statement
Does a massless string cause a normal force when attached to a wall?
Relevant Equations
F=ma probably
1702134312752.png

I'm almost certain that if it was a "steel rod" or something heavy like that, the normal (the force written in green) would exist. But does it exist for a "massless ideal string"? I mean, there is tension in the string of course, but would that cause the normal perpendicular to the wall?
 
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At the point of attachment the string exerts tension that is directed along the string and away from the point of attachment (you can't push with a string). This tension has a normal component and a component parallel to the surface. It's not the weight of the string that is the cause of this force but the weight of the ball hanging at the other end of the string that keeps the string taut. If you remove the ball, the string will go limp and exert no force if it is massless.
 
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Would the cart shown in the attached diagram remain where represented when "there is tension in the string of course"?

Spehre cart.jpg
 
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