A body of mass 25kg, moving at 3ms-1 on a rough horizontal floor is at rest after sliding through a distance of 2.50m on the floor. Calculate the co-efficient of sliding friction. [g = 10.0ms-2]
- 0.09
-
0.18
- 0.36
- 0.54
The correct answer is: B
Explanation
a = \(\frac{v^2 + u^2}{2s} = \frac{0^2 + 3^2}{2 \times 2.5}\) = 1.8m/s2
F = ma = 25 x 1.8 = 45N
N = mg = 25 x 10 = 250
but \(\mu = \frac{F}{R} = \frac{45}{25 \times 10} = 0.18\)