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READING QUIZ. The moment of a force about a specified axis can be determined using ___ . A) a scalar analysis only B) a vector analysis only C) either a scalar or vector analysis D) None of the above. z. F. A. r. A. u a. B. x. READING QUIZ.
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READING QUIZ The moment of a force about a specified axis can be determined using ___ . A) a scalar analysis only B) a vector analysis only C) either a scalar or vector analysis D) None of the above.
z F A r A ua B x READING QUIZ In the sketch, if ua represents the unit vector along line AB, the moment of force F about line AB, expressed in the Cartesian vector form, can be obtained using the formula Ma = __________ . A)(ua r ) · F B)ua· ( r F ) C) ua· ( r F ) ua D) ua· ( r F )·ua y
CONCEPT QUIZ If the line of action of force F is parallel to any specified axis a-a, the magnitude of the moment of F about axis a-a is __ . A) zero B) at a maximum C) the force multiplied by the shortest distance from the force line of action to the axis D) None of the above.
z A 3´´ 4´´ F=100 lb 6´´ B x CONCEPT QUIZ The moment of force F about line AB is A) 300 in·lb B) 400 in·lb C) 0 D) None of the above. y
ATTENTION QUIZ If the moment of a force about a point A is MA= {10 i + 2j} N-m , its moment about line AB, whose unit vector is UAB = 0.6 i - 0.8 k , has a magnitude of ___ . A) –1.6 N-m B) 1.2 N-m C) 6 N-m D) -8 N-m
z 2'' y 3'' 1'' x ATTENTION QUIZ The moments of force F about the x, y, and z axes are ___ , respectively. A) (20, 0, 0) in · lb B) (20, 0, 30) in · lb C) (10, 20, 0) in · lb D) (10, 20, 30) in · lb F = 10 lb