Posted by amirah on .
A 1.4kg block slides across a rough surface such that it slows down with an accerleration of 1.2 m/s2. What is the coefficient of kinetic friction between the block and the surface?

physics 
Henry,
Wb = mg = 1.4 kg * 9.8 N./kg = 13.72 N.
= Weight of block.
Fb = 13.72 N. @ 0 Deg.
Fp = 13.72*sin(0) = 0 = Force parallel to surface.
Fv = 13.72*cos(0) = 13.72 = Force perpendicular to surface.
Fn = FpFk = ma,
0u*13.72 = 1.4*(1.2 = 1.68,
13.72u = 1.68,
u = 0.1224.