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Physics Class 12th Laws of Motion Physics NCERT Exemplar Solutions Class 12th Chapter Eleven

A uniform metal chain of mass m length ‘L’ passes over a massless and frictionless pulley. It is released from rest with a part of its length $' l'$ is hanging on one side and rest of its length $' L - l'$ is hanging on the other side of the pully. At a certain point of time, when $l = \frac{L}{x},$ the acceleration of the chain is $\frac{g}{2} .$ The value of x is__________.

Option 1 -

Option 2 -

Option 3 -

1.5

Option 4 -

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1 Answer

Answered by

Vishal Baghel | Contributor-Level 10

2 months ago

Correct Option - 4

Detailed Solution:

Mass = m

Length = L

$\frac{m}{L} = ?$

at $l = \frac{L}{x}, a_{c h a i n} = \frac{g}{2}$

$a = \frac{F_{P u l l i n g}}{m a s s} = \frac{(L ? l) ? g ? ? l g}{? L} = \frac{(L ? 2 l) ? g}{? L} = \frac{g}{2}$

$l = \frac{L}{4} ? x = 4$

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