A block A of mass 14 kg moves alongg an inclined plance that makes an angle of `30^(@)` with the horizontal . This block is connected to another block B of mass 14 kg by a taut massless string that runs around a massless frictionless pulley . The block B moves down with constant velocity . Calculate force of friction and coefficient of kinetic friction .

Explanation

As block B moves down with constant velocity net forve on it is zero ` :. T = m_(2) g`
Again, block A will also move with constant velocity . Thereforce , net force on A is also zero .
`T - f - m_(1) g sin 30^(@) = 0 :. F = T - m_(1) g sin 30^(@)`
`f = m_(2) g - m_(1) g sin 30^(@) = (1)/(2) m_(1) g = 68.6 N`
`mu = (f)/(R) = (68.6)/(m_(1) g cos 30^(@)) = (68.6 xx 2 )/(14 xx 9.8 sqrt(3))=0.58`
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