The torque tag has no wiki summary.
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Torque Required For a Motor to Move an Object on Wheels?
I've been attempting to calculate how much torque a motor needs to produce in order to start a stationary object on wheels moving. (The torque is being applied to the rear 2 wheels, the front 2 are on ...
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3answers
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Torque vs Moment
I was wondering, why in Newtonian physics torque is called "torque" while in static mechanics they call it "moment"?
I prefer by far the term "torque", for not only it sounds strong, but also ...
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5answers
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Why does the weighing balance restore when tilted and released
I'm talking about a Weighing Balance shown in the figure:
Press & Hold on onside of the horizontal beam and then release it. It makes some oscillations and comes back to equilibrium like shown ...
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3answers
389 views
Electric engine transmission
If we compare a petrol engine and an electric engine car, it is sufficient for the electric engine car (e.g Tesla Roadster) just to have 1 gear (forward), whereas petrol engine can have up to 7.
Why ...
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2answers
236 views
Force applied off center on an object
Assume there is a rigid body in deep space with mass $m$ and moment of inertia $I$. A force that varies with time, $F(t)$, is applied to the body off-center at a distance $r$ from its center of mass. ...
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1answer
327 views
Calculating torque in a structure
I posted this on math stack exchange but realize it is more a physics question.
I have a structure which is set up as shown in the image. A weight hangs from point A with mass $m$. Joint B is free ...
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6answers
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Why is torque not measured in Joules?
Recently, I was doing my homework and I found out that Torque can be calculated using $\tau = rF$.
This means the units of torque are Newton meters. Energy is also measured in Newton meters which are ...
3
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2answers
511 views
Unit of torque with radians?
Usually, the angular frequency $\omega$ is given in $\mathrm{1/s}$. I find it more consistent to give it in $\mathrm{rad/s}$. For the angular momentum $L$ is then given in $\mathrm{rad \cdot kg \cdot ...
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3answers
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How do I calculate DC motor speed for a given load?
Suppose I have a robot of a given mass, and I'm choosing between 2 different wheels and 2 different motors to put on it. For each wheel I have the diameter, and for each motor I know the stall torque ...
4
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1answer
900 views
finding angular velocity and regular velocity when bouncing off a surface with friction
Take the game of pong as a simple example. When you hit the ball with a paddle that has a frictional surface, the ball will spin as well as change direction according to the coefficient of kinetic ...
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2answers
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Deriving $T = F\ r = I\alpha$ for a rigid body
For a single point mass :
$\tau=F_{t}r=ma_tr=(m r^2)\alpha = I\alpha$
For multiple point masses bound together : $\sum \tau_i = (m_ir_i^2)\alpha = I\alpha$
But how do we go from that to $I\alpha = ...
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3answers
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What determines the direction of precession of a gyroscope?
I understand how torque mathematically causes a change to the direction of angular momentum, thus precessing the gyroscope.
However, the direction, either clockwise or counterclockwise, of this ...
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3answers
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What is the difference between a moment and a couple?
In mechanical engineering, the torque due to a couple is given by $\tau = P\times d$, where $\tau$ is the resulting couple, $P~$ is one of the force vectors in the couple and $d$ is the arm of the ...
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3answers
490 views
Self Balancing Unicycle
Here is a link to a video of a self-balencing unicycle. I'm curious as to how this works. In particular:
What provides the torque to keep the rider from falling over? I know it's somehow provided by ...
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0answers
258 views
Torque required to rotate a cement mixer..? [closed]
I need to design a motor to rotate a cement mixer which should mix one cubic meter. So, I calculated the required volume to be 1600 liters as it is an horizontal cylinder. Consider that the mixer ...
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3answers
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Torque required to turn a drum/barrel
I need to spec a motor to turn a mixing barrel. The barrel contains loose earth and can be filled to a maximum of 50% of its interior volume. It is a horizontal cylinder, and will rotate through its ...
