
#1
Apr1312, 09:48 PM

P: 42

I know that net torque is the sum of torques in a given situation. So take this as an example: If I used a wrench to turn a nut counterclockwise and it succesfully moves, is the net torque going to be nonzero? If so, then can someone please give me an example where the net torque can be zero.
Furthermore, if net torque is zero, does that mean the object doesn't rotate? 



#2
Apr1312, 10:31 PM

Homework
Sci Advisor
HW Helper
Thanks ∞
P: 9,215

It's no different in this regard from the linear case.
A nonzero net torque will result in an angular acceleration. When the nut starts to rotate, from stationary, it is being accelerated, so there is a net torque. But very soon it's rotating at a steady rate, so the net torque is back to zero. The torque you continue to apply is equal to the dynamic friction. In the period during which you were building up the torque, but the nut was still not yielding, your applied torque was exactly balanced by static friction. 


Register to reply 
Related Discussions  
Motor Torque, Starting Torque, Stall Torque, Load Torque  Mechanical Engineering  3  
Solve for torque? Torque = Moment of Inertia * Angular Acceleration?  Introductory Physics Homework  6  
Mechanival torque and load torque caluculation of induction motor driven submersible  Electrical Engineering  0  
Wheel torque > contact patch friction > torque  Classical Physics  1  
I'm confused with the output torque, torque developed in the armature  Engineering, Comp Sci, & Technology Homework  0 