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VCE Stuff => VCE Science => VCE Mathematics/Science/Technology => VCE Subjects + Help => VCE Physics => Topic started by: naved_s9994 on May 19, 2009, 06:41:37 pm

Title: How to do....
Post by: naved_s9994 on May 19, 2009, 06:41:37 pm: How do you attempt TORQUE questions....
I am LOST !
Title: Re: How to do....
Post by: TrueTears on May 19, 2009, 06:52:30 pm: T = Perpendicular force $\times$ distance from where the force acts to where you are taking torques from
Title: Re: How to do....
Post by: naved_s9994 on May 19, 2009, 07:02:37 pm: yea but like, can you give an example of using it on a HARD torque question.....even from textbook would be cool
Title: Re: How to do....
Post by: TonyHem on May 19, 2009, 07:06:54 pm: Give an example of a question that you can't do. Probably a bridge one?
Title: Re: How to do....
Post by: TrueTears on May 19, 2009, 07:07:55 pm: Quote from: naved_s9994 on May 19, 2009, 07:02:37 pm
yea but like, can you give an example of using it on a HARD torque question.....even from textbook would be cool
What do you mean by "hard", if you can do the basic torque questions, then the "harder" ones can be done by applying the same principles. Also if you need tension, always split it into its horizontal and vertical components.
Title: Re: How to do....
Post by: pHysiX on May 19, 2009, 10:53:51 pm: heres a basic rundown of my thought process:

1)pick a pivot point that is as convenient as possible.
2)identify all clockwise and anti-clockwise torques (a clue is to look for any remaining forces and make sure they are perpendicular to the distance from the pivot point)
*another thing to note is that the distance need not always be horizontal: eg/ some punk trying to push over a car -->there's the torque from the car's weight (horizontal distance + perpendicular weight force) and torque from the applied force (vertical distance to the roof of the car and horizontal applied force)
3)then do you calculations

hope it helps =]
Title: Re: How to do....
Post by: naved_s9994 on May 21, 2009, 04:35:53 pm: yea physix, thanks....actually problem was, at my school we did Detailed study first, then motion, then electronics....then we we did the practice Q's, I was lost on only structures....i was fine with rest..

This rundown, recounts it all - THANKS
Title: Re: How to do....
Post by: Mao on May 21, 2009, 10:23:12 pm: Quote from: pHysiX on May 19, 2009, 10:53:51 pm
heres a basic rundown of my thought process:

1)pick a pivot point that is as convenient as possible.
2)identify all clockwise and anti-clockwise torques (a clue is to look for any remaining forces and make sure they are perpendicular to the distance from the pivot point)
*another thing to note is that the distance need not always be horizontal: eg/ some punk trying to push over a car -->there's the torque from the car's weight (horizontal distance + perpendicular weight force) and torque from the applied force (vertical distance to the roof of the car and horizontal applied force)
3)then do you calculations

hope it helps =]

remember that when you calculate the torque, ALWAYS, ALWAYS, ALWAYS use the PERPENDICULAR force.
Title: Re: How to do....
Post by: naved_s9994 on May 21, 2009, 10:24:13 pm: what you mean Mao
Title: Re: How to do....
Post by: pHysiX on May 25, 2009, 04:30:05 pm: for work, we must use the force in the direction of motion. for torques, the force is one that is PERPENDICULAR to the distance. that's wat mao means =]