Questions tagged [geometry]
To be used for questions on geometry closely pertaining to physics. Includes differential geometry and Euclidean geometry. Do prefer the more specific tag differential-geometry for questions about differential geometry.
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When was the 'steradian' measure of solid angle invented, and by whom? [closed]
I am curious to know when the steradian measure of solid angle was invented or devised
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Throwing a ball in the air
When we throw a ball in the air, we know that if we do not throw it too high, then g can be held constant over the trajectory and we can approximate the curve by a parabola. However we also know that ...
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Einstein's notion of "covariant"
In his The Meaning of Relativity, pg. $11-12$, Einstein explains the notion of "covariant" along the following lines:
Consider a point $\mathbf x$ on a straight line $\mathbf x -\mathbf A=\...
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How steep is too steep to tow a caravan up? [closed]
My family plans to buy a static caravan but we have been told it may not be possible to move it from the road onto our property. The entrance to the property is a bit steep – but is it too steep to ...
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Potential of circle and $n$-gon
Consider power central fields $f \sim r^k, - \infty < k < \infty$,
and unit circle, "charged" in the sense of the field.
We will be interested in the potential within the circle,
i.e. ...
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Why does moment of inertia stop at 1/2 as solidness of a cylinder increases?
So I have two things about moment of inertia:
The I for a hoop is $I=MR^2$ and
the I for a solid disk is $I=\frac{1}{2}MR^2$
I've noticed that as "solidness" goes up from 0% (completely ...
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Finding Exterior Confining Pressure from Interior Pressure Point for a Solid Disk
Essentially, I've been wrapping the pictured object tightly with string to exert a confinement pressure on its exterior. It's been difficult however to make a good estimate of how much pressure is ...
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Is obeying the parallelogram law of vector addition sufficient to make a physical quantity qualify as a vector?
I know that obeying the parallelogram rule of vector addition is a necessary condition for vectors. But is it sufficient? In other words, can there be a quantity that is added using the method but ...
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Why are spherical shapes so common in the universe?
I have a simple question. Why are most objects in the observable universe spherical in shape? Why not conical, cubical, cuboidal for instance? I am furnishing a few points to justify this statement:
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Describing force accumulation trend of an infinite volume with evenly distributed radiative sources
I am looking for confirmation if I've built my equation properly.
My goal is to describe the change in force over time at a given point if evenly distributed radiators (in-phase or cumulative energy/...
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Modified Special Geometry of SUSY Moduli Space
It is known that the Coulomb branches of 5d $\mathcal{N}=1$ and 4d $\mathcal{N}=2$
SUSY (both have eight supercharges) satisfy special geometry. This means that there exists a holomorphic prepotential ...
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Is displacement vector always the shortest path?
I read that the displacement vector of a particle is the shortest path between its initial and final positions since it's a straight line joining the two points, this holds true for me till a 2D ...
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Why are material properties often described by symmetric tensors?
It seems to me that whenever there is some material parameter for a continuum, it is described by a symmetric tensor. This is the case for the mechanical stress tensor, permittivity of crystals, the ...
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Does the top of a wheel really move at twice the velocity of the center?
According to the physics of a wheel rolling without slipping, the topmost point moves twice as fast as the wheel.
But I tried an experiment:
Take a wheel on a table and hold a ruler horizontally in ...
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Doubt in pitch of screw gauge [closed]
I have just started learning about screw gauge and I came across this statement about pitch
The pitch is the distance between two consecutive threads of a screw which is equal to the distance moved ...
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