Questions tagged [kinematics]
The description of the movement of bodies by their position, velocity, acceleration (and possibly higher time derivatives, such as, jerk) without concern for the underlying dynamics/forces/causes.
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Why is the Four-velocity insufficient to be an arrow of time?
Question edited for clarity.
Matter has a four-velocity. One component of this velocity is always along the time axis, toward the future.
My question is; “Why isn’t this component of the four-velocity ...
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Are people aware of this Functional Causal Chain of Momentum (FCCM)? [closed]
I was pondering the nature of momentum conservation in non-ideal systems and noticed a beautiful, continuous functional/mathematical chain linking potential energy all the way to momentum. It frames ...
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Positive values of Mandelstam variable $t$
Is it possible for the Mandelstam variable $t$ to reach positive values in the quasielastic charged current neutrino-neutron scattering?:
$$\nu_{\mu} + n \rightarrow \mu^- + p$$
(don't assume that ...
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How would one find the speed at a point of a loop de loop in terms of kinematics and not energy? [closed]
I was talking with a prof about loop de loop problems and how they where usually solved in terms of energy when they mention that they could maybe be solves in terms of kinematics but that they’d ...
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What is Intuition behind the Vector Components?
I have been really confused about the vector components, I have solved many-many Mechanics Problems using the Vector Components. The confusion arises due to the way I observe the vector components. ...
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Analysing $a$ = $v\frac{dv}{dx}$ expression in 1D linear and 2D curvilinear motion cases
$a$ = $v\frac{dv}{dx}$
This is a well known formula for acceleration in 1D motion cases. And it gives total acceleration in 1D cases. Please correct me if I'm wrong.
When it comes to a general 2D ...
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Regarding internal forces' ability to cause acceleration of the centre of mass [closed]
I know that "the motion of the centre of mass of the system is not affected by the internal forces."(I don't think I need to quote sources, this is universal) So if I have a toy car that ...
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Cricket ball trajectory calculation [closed]
I want to calculate the trajectory of a cricket ball using the TV camera, and be able to model the ball after it pitches. However, I am finding it difficult to accurately get the values of bounce ...
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Charged particle motion in the magnetic field due to a long straight wire
Griffiths’ Introduction to Electrodynamics (4th Edition) invites the student to solve the motion of a particle of mass $m$ and charge $q$ moving in the magnetic field due to a long straight wire ...
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Difference between average speed & magnitude of average velocity [duplicate]
I don't understand why the car's average speed is exactly 40km/h but the magnitude of average velocity is not. Why is the magnitude of average velocity less than 40? Can you tell me what the average ...
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How is the term "average" used in classical physics?
When starting to learn elementary physics, one of the first formulas that one encounters is the formula for average velocity,
\begin{equation}
\overline{v}=\frac{\text{Displacement}}{\text{Time}}\tag1
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How does the area under the Velocity-Time graph represent the magnitude of displacement? [closed]
For constant velocities where $a=0$ the area is simply given by the area of the rectangle enclosed between the velocity and the time (i.e. $v * t = x$).
And for accelerated bodies we simply imagined ...
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Am I getting closer to the car in front if they are moving at a faster velocity but decelerating faster than me? [closed]
Let's say there is a car in front of mine on a straight motorway and its speedometer is showing 100 mph while mine is showing 80mph. But it's decelerating at 10mph/s, while mine is decelerating at ...
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Mathematical definition for unit vector along the rotational axis
Is the unit vector along the axis of rotation ($\hat n$) defined as, $ \hat n=\frac {\vec r \times \vec v}{|{\vec r \times \vec v}|}$ for an rotating object in clock-wise rotation and $\hat n=\frac {\...
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Is there an upper limit to acceleration?
Dr. Blitz, a physicist and YouTuber stated that due to kinematic equations on how a spaceship would contract if it was going very fast shows us that the back of the ship cannot accelerate infinitely. ...
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