Atwood Machine and the Work done

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In the discussion about the Atwood machine with masses of 2kg and 3kg, the focus is on calculating the work done by gravity during the fourth second after release. The user initially calculated the work done as 67 joules but expressed uncertainty about the displacement and the signs of work for each mass. It was clarified that one mass moves up while the other moves down, affecting the net work calculation. The user acknowledged a mistake in their understanding and expressed gratitude for the clarification. The conversation emphasizes the importance of considering direction and displacement in work calculations.
animesh27194
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The two block in an atwood machine have masses 2kg and 3kg. Find the work done by gravity during the fourth second after the system is released from rest.I have attached my attempt here..Kindly tell me where I went wrong.
I am sure that I didnt go anywhere wrong in finding the acceleration and the displacement. But, I am doubtful abt the work done part. The answer is coming out to be 67 joules. :confused:
 

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animesh27194 said:
Find the work done by gravity during the fourth second after the system is released from rest.
What's the displacement during the fourth second? (That's from t1 = 3 s to t2 = 4 s.)

Also realize that one mass moves up while the other moves down, so the work done on each will have a different sign. Presumably, you want the net work done?
 
Last edited:
ooooh! I am so sorry...! THat's a silly mistake..! :P
 
See also the comment I added to my last post.
 
THanks a lot! I understood the concept... :)
 

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