Engg Mechanics
posted by Kishore on .
Blocks A and B of weight 200N and 100N respectively, rest on a 30 inclined plane and are
attached to the post which is held perpendicular to the plane by force P, parallel to the plane,
as shown in fig. Assume that all surfaces are smooth and that the cords are parallel to the
plane. Determine the value of P. Also find the Normal reaction of Blocks A and B.

Resolve forces parallel to the plane:
P=(m1+m2)g cos(θ)
where
P=force up the plane
m1,m2 = masses of the blocks
Normal reactions of blocks are
m1g sin(θ)
and
m2g sin(θ)
unless blocks are piled up.
(confirm with your figure)