Weight lifter uses of force to lift the dumbbell.

Weight lifter force arm is of length.

She is being bicep curl with her elbow bent at 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.

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

Vector representing the force applied to lift the dumbbell is .

Position vector of the elbow of the weight lifter is .

.

Vector representing the torque about the weight lifter elbow is . 

Vector representing the torque about the weight lifter elbow is .

Vector representing the torque about the weight lifter elbow is .