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Two identical blocks `A` and `B` each of weight `20N` are placed on a frictionless horizontal plane. The portion of the string connected to `B` is vertical and that connected to `A` makes an angle of `53^(@)` with the plane . The minimum horizontal force `F` required to lift the blocks `B` is

A

`12N`

B

`16N`

C

`32N`

D

`36N`

Text Solution

Verified by Experts

The correct Answer is:
A
Ans. (1)
`Tcos53^(@)=F` & `T=20`
`rArr20xx(3)/(5)=FrArrF=12N`
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