Answer:
-0.3
Explanation:
F' = μmg ........... Equation 1
Where F' = Frictional force, μ = coefficient of kinetic friction, m = mass of the stone, g = acceleration due to gravity.
But,
F' = ma ............ Equation 2
Where a = acceleration of the stone.
Substitute equation 2 into equation 1
ma = μmg
dividing both side of the equation by m
a = μg
make μ the subject of the equation
μ = a/g............... Equation 3
From the equation of motion,
v² = u²+2as................. Equation 4
Where v and u are the final and the initial velocity respectively, s = distance.
Given: v = 0 m/s (to rest), u = 8.0 m/s, s = 11 m.
Substitute into equation 4
0² = 8² + 2×11×a
22a = -64
a = -64/22
a = -32/11 m/s² = -2.91 m/s²
substitute the values of a and g into equation 3
μ = -2.91/9.8
μ = -0.297
μ ≈ -0.3
