Find the acceleration of the two blocks . The system is initialy at rest and the friction are as shown in fig .Given `m_(A) = m_(B) = 10 kg`

Explanation

`f_(max) = 50 N`

If they move together
`a = (120)/(20) = 6 ms^(-2)`
Check friction on B

`f_(B) = 10 xx 6 = 60 N`
`60N gt 50 N`(therefore required gt available)
Hence they will not move together

Hence they move separately so kinetic friction is involved

`:. f or a_(A) = (120 - 50)/(10) = 7.0 ms^(-2) rArr a_(B) = (50)/(10) = 5 ms^(-2) `