An object with a mass of #6 kg# is on a plane with an incline of # - pi/6 #. If it takes #18 N# to start pushing the object down the plane and #1 N# to keep pushing it, what are the coefficients of static and kinetic friction?

1 Answer
Feb 16, 2016

#mu_s =( 3sqrt3)/10#
# mu_k = 1/(20sqrt6)#

Explanation:

#f = mu N#

#N = mgcos theta = mg sqrt3/2#

Now that we have our prerequisites
Lets consider the static case first

#18 = mu mgsqrt3/2#
#18 = mu 4 * 10 sqrt3/2#

Solving we get

#mu_s =( 3sqrt3)/10#

Lets consider the kinetic case

#1 = mu_k * 4*10*sqrt 3/2#

Solving we get

# mu_k = 1/(20sqrt6)#