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--- 183_notes:torque [2014/11/21 15:55] – caballero
+++ 183_notes:torque [2015/10/14 15:45] – [The Net Torque Causes Changes in Rotation] caballero
@@ Line 1: / Line 1: @@
 ===== Torques Cause Changes in Rotation =====
-Until now, you have worked with forces and work to explain and predict object motion. You've even used [[183_notes:rot_ke|work and energy to begin to explain that objects can rotate]], but you haven't yet unpacked how that occurs -- only that a system can share energy between translation and rotation. In these notes, you will read about torque, which is a force applied at a distance from a specific point that causes a twisting or rotating about that point.
+Until now, you have worked with [[183_notes:mp_multi|forces]] and [[183_notes:work|work]] to explain and predict the motion of objects. You've even used [[183_notes:rot_ke|work and energy to begin to explain that objects can rotate]], but you haven't yet unpacked how that occurs -- only that a system can share energy between translation and rotation. In these notes, you will read about torque, which is a force applied at a distance from a specific point that causes a twisting or rotating about that point.
 ==== Lecture Video ====
@@ Line 59: / Line 58: @@
 $$\vec{\tau}_A = \langle 0,0,r_xF_y-r_yF_x\rangle$$
-Notice that if the lever arm point in the same (or precisely opposite directions) the torque is zero. The cross product of two parallel or anti-parallel vectors is zero.
+Notice that if the applied force and the lever arm point in the same (or precisely opposite directions) the torque is zero. The cross product of two parallel or anti-parallel vectors is zero.
 ==== Sign of the Torque comes from the Right-Hand Rule ====
@@ Line 73: / Line 72: @@
 ==== The Net Torque Causes Changes in Rotation ====
-Just like you read for forces, there can be multiple torques applied to an object. That is, there might be forces applied at different locations an in different directions, which could (one their own) give rise to different rotations. The concept of a net torque is an important one because it helps you decide what the rotation will be (or even if there will be any rotation). The net torque is the vector sum of all the torques acting on an object. These torques must be computed around the same rotation axis (i.e., the lever arm for each force can be different, but this lever arm must be measured from the same rotation location).
+Just like you read for forces, there can be multiple torques applied to an object. That is, there might be forces applied at different locations and in different directions, which could (on their own) give rise to different rotations. The concept of a net torque is an important one because it helps you decide what the rotation will be (or even if there will be any rotation). The net torque is the vector sum of all the torques acting on an object. These torques must be computed around the same rotation axis (i.e., the lever arm for each force can be different, but this lever arm must be measured from the same rotation location).
 $$\vec{\tau}_{net} = \sum_i \vec{\tau}_i$$
-The sign of each torque is incredibly important for determining the net torque. It is the net torque that causes changes in rotation, just like it is the net force that causes changes in translation.
+The sign of each torque is incredibly important for determining the net torque. It is the net torque that causes changes in rotation, just like it is the [[183_notes:momentum_principle|net force that causes changes in translation]].