Physics

Problem

1.5\,\text{kg}

block slides down a rough plane inclined at

25^\circ

to the horizontal. After

3\,\text{s}

of motion, its speed is

4.2\,\text{m\,s}^{-1}

. Calculate the coefficient of kinetic friction between the block and the plane. (Take

g = 9.8\,\text{m\,s}^{-2}