An old wooden telephone pole with a single cross member was blown off center during a recent storm. To temporarily stabilize the telephone pole, a repair crew has attached a cable from the end of the cross member to an eye-ring stake anchored in the ground. (Figure 3) If the origin O of a coordinate system is placed where the pole A(-1.35,-1.25,13.0) meets the ground, the point where the cross member is attached to the pole is and the point where the cable is attached to the end of the cross member is B(-1.35,-1.25,14.5) . The cable's direction is (1.00i,-1.00j,-1.00K) and it has a tension of 925N . What is , the moment that tends to twist the telephone pole due to the tension in the cable applied at point B?
The Attempt at a Solution
moment= r X T
r is the distance between A and B.
r= position vector of B- position vector of A
This is where i hit a wall and dont know where to go. Please help me :(