Now consider a woman standing on the ball of her foot as shown. A normal force of magnitude N acts upward on the ball of her foot. The Achilles' tendon is attached to the back of the foot. The tendon pulls on the small bone in the rear of the foot with a force F. This small bone has a length x, and the angle between this bone and the Achilles' tendon is phi. The horizontal displacement between the ball of the foot and the point P is D. Find Torque_N about point P due to normal force. Express in terms of N and any other quantities given. So, help?