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Two blocks of mass 10 kg and 30 kg are k...

Two blocks of mass `10 kg` and `30 kg` are kept as shown in the figure. The surface between the block is fricitional while the ground is smooth. A horizontal force of magnitude `60 N` is applied horizontally on the upper block. Find the frictional force on block of mass `30 kg` ?

A

`20 N`

B

`30 N`

C

`45 N`

D

`50 N`

Text Solution

Verified by Experts

Let the both blocks are moving together, then
`a=(60)/(40)=1.5 m//s^(2)`.
thus, force on lower block has to be `F=Ma=30xx1.5=45N`
Next, `f_(L)=mu N=0.5xx10xx10=50N`
Since `F lt f_(L)` , both the blocks will move together, thus force of friction `=45 N`
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