Mechanics

Given is a string connecting upper two blocks . friction is not present in both lowest blocks

#Mechanics

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Comments

@Aaghaz Mahajan bro @Steven Chase sir , is there any good method to.check easily which of these four blocks would move together and which different, in each case ? Note: I don't know answer to these parts

Kudo Shinichi - 2 years, 3 months ago

The case where all four blocks have the same acceleration is pretty easy. There are four equations and four unknowns. Then you can solve over a wide range of F (sweeping upwards) and see where one of the following three things happens first:

1) The required friction force between blocks 1 and 2 is bigger than the maximum possible value
2) The required friction force between blocks 3 and 4 is bigger than the maximum possible value
3) The tension in the rope is negative

This is the force magnitude at which the accelerations of the four blocks can no longer be equal

Steven Chase - 2 years, 3 months ago

Got it sir thx

Kudo Shinichi - 2 years, 3 months ago

Math	Appears as
Remember to wrap math in `\(` ... `\)` or `\[` ... `\]` to ensure proper formatting.
`2 \times 3`	$2 \times 3$
`2^{34}`	$2^{34}$
`a_{i-1}`	$a_{i-1}$
`\frac{2}{3}`	$\frac{2}{3}$
`\sqrt{2}`	$\sqrt{2}$
`\sum_{i=1}^3`	$\sum_{i=1}^3$
`\sin \theta`	$\sin \theta$
`\boxed{123}`	$\boxed{123}$