Which Acceleration Formula is Correct for the Larger Block in the Pulley System?

AI Thread Summary
The discussion focuses on determining the correct acceleration formula for a larger block in a pulley system, with two proposed formulas: 4mg/(M+17m) and 4mg/(M+16m). The user derived the acceleration as a = 4mg/(M + 16m) using free body equations for both the larger and smaller blocks. Despite this calculation, the textbook provides a different answer. The consensus among participants supports the user's derived formula as correct, indicating a potential error in the textbook. The conversation emphasizes the importance of showing work in problem-solving for clarity and accuracy.
dk_ch
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the acceleration of the larger block of mass M on frictionless floor of the pully system as in (fig given bmp attachment) will be
(i) 4mg/(M+17m) (ii) 4mg/(M+16m)

which answer is correct and how?
 

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Welcome to PF. Note that you must show some work before we can help you in the homework forums: i.e. fill in parts 2 and 3 on the homework template!
 


I tried to solve the problem using following two equations taking large and small block
respectively as freebodies

Ma = 4T ------(1)
mg-T = 4ma -------(2)

solving these two i get acceleration of the larger block a = 4mg/(M + 16m)

the answer given in the text is the other one. please provide me the right answer.
 


I agree with your answer.
 
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