Solving for Block's Acc, Kinetic Friction, and Speed

[Frosty_TAW]

a 3.00 kg block starts from rest @ the top of a 30-degree and slides 2.00 m down in 1.50s. Find (a) the acceleration of the block (b) the coefficient of kinetic friction between it and the incline, (c) the frictional force acting on the block, and (d) the speed of the block after it has slid 2.00 m
please help!

 

[T@P]

from what limited knowledge i have of this... all you would do is solev the for a using Newtons second law and then plug that into a kinematic eqtn (x = at^2/2) to find t and and then use Newtons second law again in another direction to solve for friction (mu)...

please tell me if you want a more quantitative result as i only listed th idea behind it...

 

[Frosty_TAW]

what was that formula again i just need a better theory behind itm that was a little fast

 

[Fookie]

for (a) use s=ut+0.5a(t2) where u=0 and s=2.0m and t=time to find a=acceleration


for (b) use
(mg sin#)-(u mg cos#)=ma

m=mass
a=acceleration from (a)
#=angle
g=9.8
u=coefficient


for (c) answer = u mg cos#

for (d) answer= u+at
u=0
a=accerletion
t=time


TADA!
OK!...now how abt a pay back @ pizza hut

 

[Frosty_TAW]

thanks a million man, that really helps me out