In physics and mechanics, torque is the rotational equivalent of linear force. It is also referred to as the moment, moment of force, rotational force or turning effect, depending on the field of study. The concept originated with the studies by Archimedes of the usage of levers. Just as a linear force is a push or a pull, a torque can be thought of as a twist to an object around a specific axis. Another definition of torque is the product of the magnitude of the force and the perpendicular distance of the line of action of a force from the axis of rotation. The symbol for torque is typically
τ
{\displaystyle {\boldsymbol {\tau }}}
or τ, the lowercase Greek letter tau. When being referred to as moment of force, it is commonly denoted by M.
In three dimensions, the torque is a pseudovector; for point particles, it is given by the cross product of the position vector (distance vector) and the force vector. The magnitude of torque of a rigid body depends on three quantities: the force applied, the lever arm vector connecting the point about which the torque is being measured to the point of force application, and the angle between the force and lever arm vectors. In symbols:
{\displaystyle \tau =\|\mathbf {r} \|\,\|\mathbf {F} \|\sin \theta \,\!}
where
τ
{\displaystyle {\boldsymbol {\tau }}}
is the torque vector and
τ
{\displaystyle \tau }
is the magnitude of the torque,
r
{\displaystyle \mathbf {r} }
is the position vector (a vector from the point about which the torque is being measured to the point where the force is applied),
F
{\displaystyle \mathbf {F} }
is the force vector,
×
{\displaystyle \times }
denotes the cross product, which produces a vector that is perpendicular to both r and F following the right-hand rule,
θ
{\displaystyle \theta }
is the angle between the force vector and the lever arm vector.The SI unit for torque is the newton-metre (N⋅m). For more on the units of torque, see § Units.
I am designing a soccer ball launcher (like the one in the attached picture) for school and am having trouble figuring out how much torque I need the motors to have.
I am trying to follow an energy analysis approach to get these calculations done. Attached is a file of my calculations so far...
From the givens:
Approximate Earth as a sphere:
##I_e = \frac{2}{5}MR^2 = \frac{2}{5}(5.97x10^{24})(6.371x10^6)^2 = 9.69x10^{37} kg*m^2##
##\omega_e = 7.29x10^{-5} \frac{rad}{s}##
To calculate the rate of precession of the disk the Earth precesses around (1 revolution every 26,000 years)...
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I recently discovered torque motors and think they would be perfect for a device I’m designing, except for the fact that the power I need isn’t available in the size I’m looking for.
I’m wondering if two or more smaller torque motors connected to the same shaft can provide the same power...
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Hello,
I know it might sound silly but sometimes I get confused.
Let's say I have a gyro-compass and I get 3 equations of torque for the 3 axes.
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These are the Euler's dynamics equation with moving reference frame...
Hello,
New here but thanks in advance for help.
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I have written the translational equilibrium on the horizontal and vertical component:
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I have a problem,
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If I torque a thread combination of M26x1,5; in brass material, with 90 Nm.
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Why?
I am working on an axial flux generator design, I consisits of 2 rotors and one stator, there are 6 pole pairs and 9 coils. Here is my simulation setup
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Hi,
This has long been in my head, I've seen it work out in reality, but I have no idea about the forces involved in this. As I don't have an engineering degree or mathematical knowledge in automotive engineering, I've come here for help. Sorry if I've used some terms where they do not fit, as...
Hello all:) thanks for the help. This is for my fluids class. This is an example problem and I am stuck on it.
ok, so i found a video on youtube which walks through the entire process, but I am confused at a few sections. Here is the link to the video so you can follow:
at time stamp 2:37...
Apologies if this is in the wrong section as it isn't particularly medical in nature despite it being about the body.
I am currently conducting a rapid review with outcomes of knee muscle strength. This is measured by biodex dynamometry, which assesses numerous values including Peak moment...
Hi All,
I must calculate the torque and for an agitator motor. An anchor type agitator/scraper, removing crust off the edge of a tank.
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I came across this 'problem' when I was trying to think about how a torsion spring would apply torque in something like a miniature catapult.
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I apologize in advance for any errors in my concepts or assumptions. Feel free to correct me wherever I am wrong. Thanks in advance for the help.
There is a vertical shaft which will be operated at around 600 rpm (N) which can be achieved in 2 seconds (or even 4 just an assumption). The shaft...
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I would like to calculate (roughly) how much torque is needed bringing the blue plateau in movement. Assume the blue plateau is loaded with 7.5 kg. The radius of the blue circle is 100 mm.
Kleppner and Kolenkow say "Consider a gyrocompass consisting of a balanced spinning disk a light frame supported by a horizontal axle. The assembly is turntable rotating at steady angular velocity Ω. There cannot be any torque along the horizontal AB axis because the axle is pivoted".
I'm not...
Hi guys,
The purpose of this post is to understand the actual phenomenon behind torque production in eddy current motors. This query is based on theoretical principles of torque production in AC motors.
Consider a simple eddy current AC motor with a disc type or cylindrical rotor (Watthour...
Question : I start by putting the image of the problem from the book. The water surface is given to run along the (top) edge of the bridge.
Attempt : The crux of this problem lies in the fact that the pressure of water against the gate will vary along its depth ##h## as ##\rho gh##. This makes...
Alright how do I explain this. I am looking for the true and absolute equation of torque, specifically, the ratio of angular acceleration to torque.
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Hello,
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Hello all,
I need some help with a problem at statics, friction applied on threads. A threaded screw is given a ("horizontal") force of 100 N at the end of the handle. As the exercise states, they ask to calculate the force which occurs at the tube as well as the force needed to vise handle to...
I'm thinking of ways I could increase the torque on my servo motors without changing the overall size too much. So far the only idea that comes to mind is replacing the small motor that drives it with a slightly bigger motor that has more windings, would that help?
Below is an ideal mass pulley system that we encounter in many problems under Newton's Second Law of Motion questions.
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I am reviewing this problem from my textbook and am having some trouble with it. When solving for ΣTorque I chose the hinge to be the axis of rotation. I understand that from this point if the board is being held up and it were to fall after removing support, mg (the center of mass of the board)...
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Thanks
Hi everybody
I have 4 wheel robot like car .
2 stepper motors that one is in front and other is in rear of robot and these motors directly connected to wheels. so two of other wheels is not connected to motors.
this robot move straight and curve.
i want to find the formula that calculate...
Summary:: Please see the attached photo.
I have obtained the correct answer, and my solution agrees with the official solution. However, I have some questions about why the solution is correct. (One may have to draw out some diagrams for this problem, it was quite hard to visualise for me.)...
Hi everyone,
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m = total mass of vehicle
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Summary:: accelerometer Vs gyroscope - measuring torque
Torque can be measured with an accelerometer (tangential-acceleration):
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t = m*a*r Nm
Torque can be measured with an gyroscope (angular-acceleration):
t = F*r
The...
My guess is (c) since the rest of the options do not make sense to me but I am not sure about the shape of the graph.
Is (c) the correct answer? If yes, how to know whether the shape will be like in the option (straight line then curve downwards) or other shape like straight line only (like y =...
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Maybe it is...
I have trouble solving this problem any help would be appreciated.Problem statement
##J=\frac{mr^2}{2}##
a) Determine the motion of yoyos for ##n=1,2,3##
The case for ##n=1## is simple, however, I am having trouble with ##n=2## and ##n=3##.
for ##n=2## I started by drawing all the forces...