If a 4 kg4kg object moving at 16 m/s16ms slows down to a halt after moving 800 m800m, what is the friction coefficient of the surface that the object was moving over?

1 Answer
Jun 2, 2016

mu_k=0.013" has no unit"μk=0.013 has no unit

Explanation:

v_f^2=v_i^2-2*a*Delta x

v_f=8" "m/s

v_i=16" "m/s

Delta x=800" "m

a:"acceleration of the object"

8^2=16^2-2*a*800

64=256-a*1600

1600*a=256-64

1600*a=192

a=192/1600" "m/s^2

F_f=mu_k*cancel(m)*g=cancel(m)*a

mu_k="coefficient of friction"

mu_k*g=a

mu_k=a/g

mu_k=(192/1600)/(9.18)

mu_k=192/(1600*9.18)

mu_k=192/14688

mu_k=0.013