Torque The lever arm is the perpendicular distance from the axis of rotation to a line drawn along the direction of the force t=Fd= FL sin Fsinφ F F Fcosφ The sign of the torque is positive if its turning tendency is counterclockwise and negative if its turning tendency is clockwise(right-hand rule) Physics 121: Lecture 17, Pg 2Physics 121: Lecture 17, Pg 2 Torque The lever arm is the perpendicular distance from the axis of rotation to a line drawn along the direction of the force  = Fd = FL sin  d  L F  L F  F cos  F sin  The sign of the torque is positive if its turning tendency is counterclockwise and negative if its turning tendency is clockwise (right-hand rule)