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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Toilet paper dilemma
There are two ways to orient the toilet paper: "over" (left image), "under" (right image).
Each has it's pros and cons. For some reason, it's always easier to tear off the paper ...
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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. Work & Energy are also measured in Newton ...
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Apparent Violation of Newton's $3^{\text{rd}}$ Law and the Conservation of Momentum (and Angular Momentum) For a Pair of Charged Particles
Consider a system of the two identical positive point charges situated in free space (isolated from the influence of any other external fields) as shown in the attached diagram. Particle $1$ is at $(a,...
user87745
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Hanging a hammer from a table and a stick so that its midpoint is outside of the support of the table
I came across this pic on the internet today. At beginning I thought it is just not possible because the centre of mass is way off so gravity will generate torque making the stick and hammer fall. ...
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Is torque as fundamental a concept as force?
I used to think that torque and force were equally “fundamental”. In other words, my understanding was that we usually use Cartesian coordinates in many common problems because it is a convenient ...
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Is Nm the same unit of torque as mN?
A couple of days ago, I noticed that the torque unit used by my teachers is $mN$, and while reading on the internet it came to my notice that in all textbooks the official unit is $Nm$.
I asked one ...
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Why is it easier to handle a cup upside down on the finger tip?
If I try to handle a tumbler or cup on my fingertip (as shown in fig), it is quite hard to do so (and the cup falls most often).
And when I did the same experiment but this time the cup is upside ...
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Why are arched bridges stronger than flat bridges?
To keep the question brief: in bridge design, why is the arch structure favoured compared to a simple flat one?
In other words, how does the curved platform alter the force decomposition of the load ...
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What causes a rotating object to rotate forever without external force—inertia, or something else?
Someone told me that it is not inertia, but I think it is inertia, because it will rotate forever. In my understanding, inertia is the constant motion of an object without external force. Am I wrong?
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Why is there a size limitation on animals?
Why is there a size limitation on human/animal growth? Assuming the technology exists for man to grow to 200 feet high, it's pretty much a given that the stress on the skeletal structure and joints ...
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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 in ...
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Are force vectors members of a vector space?
Vectors in vector spaces depend only on their size and direction.
Force vectors, for example, depend also on their location. Opposite force at different locations, for example, do not annihilate each ...
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Why does torque point perpendicular to direction of the motion?
I have an intuition problem calculating torque using the cross product formula. As for example let the magnitude of the force be 50 lbs and length of the wrench be one foot and you are exerting ...
user86411
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How does a twisted piece of string/yarn wind back on itself? What kinds of forces are responsible for this?
I do a lot of fibrework (carding wool, spinning yarn, weaving, etc.) and I've noticed a funny behaviour that anything long and flexible, which can withstand significant torque exhibits. If I take a ...
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Plank overhanging off a building — where does the normal force go?
Suppose there is a (uniform rectangular) plank of mass $m$ and total length $L$ that is on top of a building with some piece overhanging or jutting out past the building. Assume it isn't past the ...
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