CSS Forums

CSS Forums (http://www.cssforum.com.pk/)
-   Physics (http://www.cssforum.com.pk/css-optional-subjects/group-ii/physics/)
-   -   Difference between torque and moment. (http://www.cssforum.com.pk/css-optional-subjects/group-ii/physics/59577-difference-between-torque-moment.html)

azure Sunday, January 29, 2012 05:37 PM

Difference between torque and moment.
 
Is there any difference between torque and moment?
According to my understanding both are same.
Both produce turning effect and both measured as force into distance.
Does that mean torque and moment are two names of the same phenomenon?

azzee Monday, January 30, 2012 08:30 PM

torque=moment=moment of force

azure Monday, January 30, 2012 09:07 PM

okk! so torque and moment , are one and the same thing and can be used interchangeably. is it so?

ravaila Monday, January 30, 2012 09:22 PM

torques are moment but not all moments are torque
torque is tunneling effect with revolutions like around a pivot .moment is also for non-revolutionry system

azure Monday, January 30, 2012 10:36 PM

"torques are moment but not all moments are torque"
Could you please elaborate this point?
-
What i understood, a force is applied on a pivot, the turning effect produced is torque.
And what if a force is applied on a structural member, say beam, will torque be produced in it too? In engineering, we use , moment is produced in the beam. Does this moment = torque?

marslanqaisar Monday, January 30, 2012 11:21 PM

Although I'm not science student but i'll try to explain
 
[B]Torque, moment or moment of force[/B], is the tendency of a force to rotate an object about an axis,fulcrum, or pivot. Just as a force is a push or a pull, a torque can be thought of as a twist.
Loosely speaking, torque is a measure of the turning force on an object such as a bolt or a flywheel. For example, pushing or pulling the handle of a wrench connected to a nut or bolt produces a torque (turning force) that loosens or tightens the nut or bolt.

[CENTER][IMG]http://upload.wikimedia.org/wikipedia/commons/0/09/Torque_animation.gif[/IMG][/CENTER]


Torque and moment are often used interchangeably. Most people are confused when asked the difference between moment and torque. The terms torque and moment originated with the study conducted by Archimedes on levers. Torque (most commonly used) or moment (used by engineers) is a concept of turning force. This turning force is applied when we push a door or try to open a nut using spanner. Both the door and the spanner turn about a point called the pivot or fulcrum. The force that is applied is at some distance from this fulcrum. The turning effect of the force applied depends upon this distance from the pivot or fulcrum.

[B]Moment = Force* Perpendicular distance from the pivot[/B]

From this equation, it is clear that if we want to complete the task using less force, we have to increase the distance from the pivot.
In contrast, when a car driver turns a steering wheel, he exerts two equal and opposite forces on the steering. These forces form a couple and the turning effect of this couple is the sum of the moment of the two forces. [B]The moment of a couple is called Torque.[/B]

[B]Torque= Force*Perpendicular distance between the two perpendicular forces[/B]

In common parlance, Torque and moment are used interchangeably. Torque, or the moment of a force is its ability to rotate an object about an axis. While force is applied in torque as well, force is a push or a pull but in torque this force is in the form of a twist.

Your answer

[B]For the students of mechanical engineering, the two terms are different and not interchangeable. In general [U][SIZE="3"]moment[/SIZE][/U] is the term used when referring to the ability of a force to turn an object about its axis. [U][SIZE="3"]Torque[/SIZE][/U] is a special application of moment. When there are two equal and opposite forces, they form a couple, and the moment that results is called a torque. Here the applied force vectors are zero.[/B] :D

ishtiaqahmad85 Monday, January 30, 2012 11:29 PM

do not worry about the difference
at this stage u just have to memorize the definition.
Momentum is the product of mass and velocity that is P = mv its unit is Kg.m/sec
Torque can be defined as the turning effect of a force
if u are asking of difference then in simple words torque deals with rotation and momentum with linear motion
f u need more explainantion u can ask

ishtiaqahmad85 Monday, January 30, 2012 11:37 PM

torque and momentum are not the same
 
[QUOTE=ravaila;399032]torques are moment but not all moments are torque
torque is tunneling effect with revolutions like around a pivot .moment is also for non-revolutionry system[/QUOTE]

torque is the turning effect and momentum is quantity of motion in a body
these are entirely different things
although torque is the rotational analogue of force, it have no such relation with momentum.
torque is denoted by T(ta) having a unit of N-m
T= r * F(r= moment arm, F= force)
momentum is denoted by P
P = mv(m= mass, v= velocity)

azure Tuesday, January 31, 2012 01:54 AM

umm okk thankyou guys.
-
@ ishtiaqahmad85.
I was asking about torque and MOMENT, not momentum.
Anyhow thankyou all for your answers.
-
And i had to worry about this difference as it came to my mind a couple of days ago and since then it has been bugging me to the extent that i couldn't concentrate on anything else! :(

ishtiaqahmad85 Tuesday, January 31, 2012 10:59 AM

yar i could understand moment
r u asking for moment arm????
brother im trying to answer ur question satisfactorily but for that u have to explain ur question
i advised u because there are certain concepts which can not be cleared this time rather their details would confuse u further


11:03 AM (GMT +5)

vBulletin, Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.