What is the true definition of torque?

Just wondering because there's so many math equations relating to it. Force x Distance, Inertia x Angular Acceleration and in one problem I saw people using torque to describe how to balance people on a seesaw with units of kg-m. ????What is the true definition of torque?
Hello,





I don't know if this is the ';true definition';, but it is the way that I like to explain the concept.





Torque is really a twisting force. Torque is created whenever a force and its reaction force are NOT COLINEAR (on the same line).





Lets say you have a Force on the left end of a seesaw, like a child's weight. (There is another child on the other end, so the system is in equilibrium.) You must have an ';equal but opposite'; force to oppose the child's weight, right?. But it cannot act directly in line with child's weight. It acts through the fulcrum, some distance from the child's weight.





So not only does the weight create another force at the fulcrum, it also creates a torque around the fulcrum, trying to twist the seesaw counter-clockwise. Equilibrium would demand that the product of the other child's weight times the distance create an ';equal but opposite'; torque.





Now, about the kg-m, that is just technically wrong. They should have converted mass to weight to really be getting torque, of course. This shortcut worked for them because they were dealing with a ratio of forces (times distance) and instead they got a ratio of masses (times distance). But because weight is proportional to mass (g is constant), the ratios gave equal results.





Good Luck crazy girl





Oh, and calculating torque from ';Inertia x Angular Acceleration'; is just the same as F = m * a., but in angular terms. (The ';Torque = Force * distance'; is only a way to convert back and forth between translational and rotational systems.)





There are equivalent rotational equations for all of the translational equations that you have learned so far.





F becomes torque (T)


V becomes angular velocity (w)


a becomes angular acceleration. (alpha)


m becomes moment of inertia.(I)


distance moved (S) becomes angles turned (theta).


etc..


Only time is unaffected.





For example,


F = M*a becomes T = I*(alpha)


V2=V1+a*t now becomes w2=w1+(alpha)*t.


S = (1/2)*(V2+V1)*t becomes (theta) = (1/2)*(w2+w1)*t





Good LuckWhat is the true definition of torque?
Torque is simply a measure of turning or twisting power. IE crankshafts, driveshafts. A hydrualic cylinder ,for example does not have any torque specifications because all that they do is either push or pull. The motor that ';turns'; the hydraulic pump that runs the cylinder however, is measured in torque. Also all nut and bolts are tightened according to ';torque'; usually in ';foot pounds';. I don't know about the seesaw thing though. hhhhmmmmmm.