Pulley Question : find tension in rope (Help )

AI Thread Summary
The discussion revolves around calculating the tension in a rope connected to a 6 kg block. Initially, the user calculated the tension (T2) using the gravitational force component but neglected to account for acceleration. After clarification, they realized the importance of summing the forces and setting them equal to the net force (Fnet) to find the correct tension. The user ultimately arrived at a revised answer of 41. Emphasis is placed on the importance of clear free body diagrams and accurate equations in solving such problems.
Lori

Homework Statement


upload_2017-11-12_16-21-11.png


Homework Equations



F = ma

The Attempt at a Solution


So , i drew a freebody diagram for the 6k gram block, and the tension to the right of I call T2.
Therefore, the force of gravity component parallel to T2 is (6*9.8)sin30. Therefore, T2 is equal to this value which i found is 29.4! However, i don't think this is right!
 

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Lori said:
However, i don't think this is right!
You think correctly: you forget about the acceleration...
 
BvU said:
You think correctly: you forget about the acceleration...
what do you mean? :(

I see... i got the answer 41. I had to set netforce for each of them to ma
 
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He is saying that you neglected to include the acceleration.
 
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Dr.D said:
He is saying that you neglected to include the acceleration.
i realized that i should be take the sum of the forces on each object and setting it equal to the Fnet. I only realize this till now! Few more hours until the exam :(!
 
Lori said:
i realized that i should be take the sum of the forces on each object and setting it equal to the Fnet. I only realize this till now! Few more hours until the exam :(!
In these questions first try to make free body diagram clearly and then write equation accordingly.
 

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