I
about B is 120 lb-in. clockwise, determine the value of $\alpha$.
3.9 Rod AB is held in place by the cord AC. Knowing that the tension
in the cord is 1350 N and that $c = 360$ mm, determine the moment
about B of the force exerted by the cord at point A by resolving that
force into horizontal and vertical components applied (a) at point A,
(b) at point C.
3.10 Rod AB is held in place by the cord AC. Knowing that $c = 840$ mm
and that the moment about B of the force exerted by the cord at
point A is 756 N\text{-}m, determine the tension in the cord.
3.11 and 3.12 The tailgate of a car is supported by the hydraulic lift BC.
If the lift exerts a 125-lb force directed along its centerline on the
ball and socket at B, determine the moment of the force about A.
A
15.3 in.
450 mm
Fig. P3.9 and P3.10
C
B
C
240 mm