A package of mass 6 kg is held at rest at a fixed point \(A\) on a rough plane. The plane is inclined at \(30 ^ { \circ }\) to the horizontal. The package is released from rest and slides down a line of greatest slope of the plane. The coefficient of friction between the package and the plane is \(\frac { 1 } { 4 }\). The package is modelled as a particle.
Find the magnitude of the acceleration of the package.
As it slides down the slope the package passes through the point \(B\), where \(A B = 10 \mathrm {~m}\).
Find the speed of the package as it passes through \(B\).