91_Problem CHAPTER 9 - PROBLEM 9.79 CONTINUED(a = 45 I x =...

PROBLEM 9.79 CONTINUED
( a )
4 4 4
5 3 1
45 : cos90 sin90
16 16 2
x
I a a a θ π π
′
= + ° = − ° − °
4
or 0.482
x
I a
′
= W
4 4
5 3 1
cos90
16 16 2
y
I a a π π
′
= + ° +
4
or 1.482
y
I a
′
= W
4 4
3 1
sin90 cos90
16 2
x y
I a a π
′ ′
= − ° + °
4
or 0.589
x y
I a
′ ′
= − W
( b ) 30 : θ = − °
( ) ( )
4 4 4
5 3 1
cos 60 sin 60
16 16 2
x
I a a a π π
′
= − − ° − − °
4
or 1.120
x
I a
′
= W
( ) ( )
4 4 4
5 3 1
cos 60 sin 60
16