Questions tagged [torque]
This tag is for questions regarding to torque, which is a measure of the increase in angular momentum over time.
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Why is the internal torque zero?
In an object, the forces that two particles exert on each other are equal and opposite to each other and the resulting torque on the particles are equal and opposite to each other.but we know that ...
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Reference frame used to calculate torque in $\boldsymbol{\tau} = \mathbf{r}\times\mathbf{F}$
I know that in $\tau = I \alpha$, we are present in frame of axis. When we write $\boldsymbol{\tau} = \mathbf{r}\times\mathbf{F}$, are we present in the frame of the point about which torque is to be ...
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How to interpret the additive term in torque formula?
Torque formula for a body subjected to a force is: $\vec{M}$ = $\frac{\mathbb d\vec{L}}{\mathbb dt}$ + $\vec{v}_o$ $\times$ $\vec{p}$; where $\vec{M}$ is the torque, $\vec{L}$ is the angular momentum, ...
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In gyroscopic effect of a quadcopter, why does precession cause torque, not vice versa?
I don't know if the header corresponds to my actual quest but i will explain.
In quadcopter dynamic equations of Newton-Euler formation that I have encountered in all academic publications, torque ...
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Alignment and anti-alignment of spins in magnetic field
Let's say that we spins in a very strong magnetic field. Then, the spins want to align in the same direction as the magnetic field due to torque being exerted on the spins. However, it may happen that ...
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Dropping a stick down with an angle
Let's say that we drop a stick down with an angle, meaning that the stick is not parallel to the ground. Assume there is only gravity. Is it correct that the orientation of the stick will not change ...
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When a wheel begins to roll on a flat surface, is it due to fulcrum generated at the contact point by friction?
[Edit: What I'm trying to understand is how any wheel rolls on a surface, instead of just spinning in place. I know that friction provides the force to make the wheel roll, but I'm unsure about the ...
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Angular acceleration of a pulley [closed]
This is the way I solved but the answer seems to be different.
Torque = $Iα$
Torque = $Mgr-\dfrac{Mgr}{2} = \dfrac{Mgr}{2}$
$\dfrac{3}{4}Mr^2 = \dfrac{Mgr}{2}$
Cancelling things give, $α = \dfrac{2g}{...
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How do objects move in a linear path if you can never apply a force to the center of mass of it?
When you apply a force to an object, you are applying it to somewhere other than the center of mass since you cannot perfectly push it to the point. Centimeters, millimeters, micrometers---whatever it ...
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Torque at only two points of contact between a rope and a disk (rigid body dynamic)
In physics, particularly when dealing with rigid bodies, there's a common practice of calculating torque at only two points of contact between a rope and a rotating disk, typically at the extremes ...
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Energy conservation for a rolling rigid body
I came across this question where
A solid cylindrical body of mass m and radius r rolls without slipping over a smooth inclined plane. Its initial velocity is v. What would be the maximum height ...
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Finding the torque required to turn a cart resting on 4 wheels
I am building a cart that has two handles on the bottom face. The cart is basically a table resting on castor wheels, one on each leg. If I apply a couple on the handles, the cart will turn. I am ...
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Horizontal forces of a wheel that is rolling and slipping while subjected to a coupled moment?
I am trying to understand what's going on with this problem:
I summed the forces in the $x$-axis, which is horizontal, and I thought the moment would create a force opposing the friction force. ...
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Torque on tendon driven inverted pendulum
I have this setup of an inverted pendulum and need help figuring out the force-torque relationship.
Let's start with the left pendulum, where I inserted all values I am interested in. The red arrow is ...
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Nordic curl - force at the ankle
So, there is an exercise called nordic curl. Looks something like this: https://www.youtube.com/watch?v=_e9vFU9-tkc
It is sometimes performed with someone holding your ankles down. How does the ...
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