The discussion revolves around calculating the length of a lever arm given a specific torque and force. The context involves understanding the relationship between torque, force, and the lever arm in a physics problem related to rotational mechanics.
The discussion is ongoing, with participants offering insights into the relationships between the variables involved. Some guidance has been provided regarding the formulas, but there is no consensus on the assumptions that should be made about the angle of force application.
There is uncertainty regarding the angle of force application, which affects the calculation of the lever arm. Participants are considering different definitions of the lever arm and how they relate to the problem at hand.
That's not quite right, and neither is the problem statement very clear. if T=rFsintheta, then you need to know theta in order to solve for r, where r is the length of the lever arm, unless one assumes that the force is applied perendicular to the arm. Is theta given in the problem?kelly_kelly said:The answers are in the formulas you've posted. If lever arm = r sin theta, and torque = force * r sin theta, then torque = force * lever arm. Since you know torque and force, you can solve for lever arm.
PhanthomJay said:That's not quite right, and neither is the problem statement very clear. if T=rFsintheta, then you need to know theta in order to solve for r, where r is the length of the lever arm, unless one assumes that the force is applied perendicular to the arm. Is theta given in the problem?
I looked up the definition of 'lever arm' on several web sites, and discovered that some call it the length of the position vector between the point of application of the load and the axis of rotation (Wiki) while others call it the perpendicular distance from the line of action of the force to the axis of rotation. I tend not to trust Wiki most of the time (they take a simple topic and make it as complex as is humanly possible), so let's go with the latter. In which case the lever arm is __________(fill in the blank).DeeAussie said:Everything I listed was what was given so I guess you do have to assume perpendicular?