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Two block A and B are placed one over ot...

Two block `A` and `B` are placed one over other. Blocks `B` is acted upon by a force of `20 N` which displaces it through `5 m`. Find work done by frictional force on block `A`.
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Text Solution

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The correct Answer is:
40 J
Limiting friction between the blocks
`f_(L) = 10 N`
`[a_(max)]_(A) = (10)/(2) = 5 m//s^(2)`
i.e., for shipping between `A,B,B` must move with `5 m//s^(2)`

`rArr F = 25 N`
but given `F = 20 N`.
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