Question

FORCES!!!!!! Help.

Answer 1

A 200 lbs block is at rest on a 30degrees incline. the coefficient of friction between the block and the incline is 0.20.

a)compute the value of a horizontal force P that will cause motion to impend up the incline.

Answer 2

agree so far ?

Answer 3

ok

Answer 4

and there is Normal from the inclined plane

Answer 5

so forces in y direction :
N = mgcos30 + pcos60
in x direction:
psin60 = mgsin30 + fric
where
fric = 0.2N = 0.2(mgcos30 + pcos60)
so plugging this into x direction :
psin60 = mgsin30 + 0.2(mgcos30 + pcos60)

Answer 6

now you can find p

Answer 7

wait , where did you get the pcos60 and psin 60?

Answer 8

as i understood from the question. p is horizontal.. so i decompose it to my x axis and y axis

Answer 9

look at the diagram.