Weight lifter uses 212 N of force to lift the dumbbell.

Weight lifter force arm is of 0.356 m length.

She is being bicep curl with her elbow bent at 15⁰ angle below the horizontal in the direction of positive axis.

Determine component form of each vector.

Comoponent form of the vector representing the directed distance from the axis of rotation to the end of the handle.

Comoponent form of the vector can be found by the above triangle.

Vector repesenting the force applied to lift the dumbebell is .

Postion vector of the elbow of the weught lifter is .

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Vector representing the torque about the weight lifter elbow 

The vectors are and .

Cross product of and is

Cross product of and is

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The vectors and are orthogonal if and only if .

The dot product of and is .

Find the dot product of and .

Find the dot product of and .

Thus, the is orthogonal to the both and .

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is orthogonal to the both and .