Is the Pulley Reacting to Tension in Lifting Rope?

AI Thread Summary
The discussion focuses on whether a pulley is affected by the tension in a lifting rope. It clarifies that tension is an internal force within the rope, while the rope exerts contact forces on the pulley. The tension is represented with two arrows because the forces at each end of the rope are equal to the tension, which is a scalar quantity. Different pulley setups react to tension in various ways, such as through bearings or motor torque in winch systems. Overall, the complexity of pulley arrangements prevents a single general answer regarding the reaction to tension.
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Suppose a pulley is lifting a mass through rope so the rope is applying force to mass in form of Tension. Is the rope also applying that force to pulley i.e Is pulley being acted upon by Tension??
 
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shayan haider said:
Is pulley being acted upon by Tension?
Tension is internal to the rope. The rope exerts contact forces on the pulley.
 
A.T. said:
Tension is internal to the rope. The rope exerts contact forces on the pulley.
Hm but why we express Tension by Two arrows?
 
shayan haider said:
Hm but why we express Tension by Two arrows?
Because the magnitudes of the forces exerted tangentially by the string ends are equal to the tension in the string, which by itself is a scalar.
 
Tension in lifting rope is reacted by various means depending on the set up .

Simple cases
:
Rope continues around pulley to another end which is being pulled to lift the weight
Tensions in the two rope ends are reacted by the pulley bearings .

Rope wraps around a winch drum which is being powered to lift weight .
Tension in lifting rope is reacted by torque of motor acting on drum and by drum bearings .

Too many cases of pulley arrangement to give a general answer .
 
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