What is significance of torque

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Torque is a critical concept in physics, representing the rotational equivalent of linear force. It is defined as the product of force and the distance from the pivot point (F*r), which effectively models and predicts mechanical behavior in practical applications, such as using tools or accelerating vehicles. The distinction between torque and linear force is essential, as torque relates to angular acceleration and moment of inertia, paralleling the linear motion equations. Defining torque as F*r^2 would not yield accurate results in calculations involving balance and mechanical systems. Understanding torque is vital for grasping how forces cause rotational motion in various real-world scenarios.
Arslan
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or you can say what is the physical interpertation of torque. i know the mathemetics of it but what's its significance in practical terms.
 
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What? You mean you want to know how it applies to the real world?

Like how you use a wrench to tighten a nut on a bolt? Or rev an engine to accelerate your car?
 
Using a screwdriver is a rather good way to feel what torque is.
 
let me put my question this way
why torque is defined as F*r why not F*r^2
 
Hi Arslan! :smile:

Torque is turny-force, and moment of inertia is turny-mass.

Mass is the ratio of linear force to linear acceleration …

twice the force gives twice the acceleration.​

Moment of inertia is the ratio of torque (angular force) to angular acceleration …

twice the torque gives twice the angular acceleration. :wink:
 
Arslan said:
let me put my question this way
why torque is defined as F*r why not F*r^2

Reasonable question.
The pragmatic answer is that your suggested alternative won't give you the right answer when you try to calculate what will balance what. Torque is a quantity, like Force that can be used to model and understand mechanical situations AND to predict what will happen. The proof of the pudding is in the eating.

The more rigorous answer is that angular momentum is a very basic quantity in the Universe - just as linear momentum is. The formulae for linear motion, such as
Force = mass times acceleration
momentum = mass times velocity
and others, are well known. (?)

There are equivalents in the 'rotational world' and Torque turns up in those formulae, along with Moment of Inertia and Angular Momentum etc.
You would need to read further if you want more details and some of those formulae.
 
Arslan said:
or you can say what is the physical interpertation of torque. i know the mathemetics of it but what's its significance in practical terms.

I think of torque as a force that causes rotational motion.

F = ma; here force F causes linear motion, with linear acceleration a.

Torque τ = Iα ; α is angular acceleration and moment of inertia I is related to mass.

Similarity between this 2 equations seem to be what is linear (motion in straight line) and angular (motion in circle).
 
Arslan said:
let me put my question this way
why torque is defined as F*r why not F*r^2
What would be the advantage of defining torque as F*r^2?
 

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