Probing the misconception:

The tension in a string is the sum of the forces acting on each end.

References  Description

 

Two 10 N weights are tied to the ends of a string, which is hung over two frictionless pulles, as shown below. What is the tension in the string? Explain your answer.

 

 

Students that suffer from this misconception will state that the tension in the string is 20 N.

 

Related misconceptions/student difficulties that may arise in the question:

Strings transmit (unchanged) an external force acting on one object to another object.

 

 

 

 

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