COSMOS: Complete Online Solutions Manual Organization System
Chapter 3, Solution 38.
From the solution to problem 3.37
rC/ A = 1.02 m with rC/ A = ( 0.9 m ) i − ( 0.48 m ) j
rD/ A = 1.10 m with rD/ A = − ( 0.52 m ) i + ( 0.9 m ) j + ( 0.36 m ) k
Now by definition
rC/ A ⋅ rD/ A = rC/ A rD/ A cosθ
or ( 0.9 j − 0.48k ) ⋅ ( − 0.52i + 0.9 j + 0.36k ) = (1.02 )(1.10 ) cosθ
0 ( − 0.52 ) + ( 0.9 )( 0.9 ) + ( − 0.48)( 0.36 ) = 1.122cosθ
cosθ = 0.56791
or θ = 55.4° W
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