All Questions
Tagged with conservation-laws kinematics
73
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Kinematics of a two-body decay [closed]
I suspect a flaw in the reasoning below, but am unable to pinpoint it: Is there something inconsistent in terms of the application of conservation of momentum and energy? Thanks for any hints in ...
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3
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How is momentum conserved in this collision with loosely-connected spheres?
There are three identical spheres. B and C are loosely connected with a light inextensible string, and A approaches B directly at some initial velocity $v$. There is no angular momentum.
A and B have ...
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Threshold energy formula
In Krane's Introductory Nuclear Physics, in chapter 11, he uses the conservation of energy and momentum to derive the formula for the threshold energy of a reaction a + X → b + Y (with X being an ...
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Conservation Principle
We are introduced to Principle of Conservation of Linear Momentum via the Newton's Second Law
$$\vec{F_{net}}=\frac{d\vec{p}}{dt}$$
It states when net external force equals zero then $\vec{p}=$...
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What happens to velocity if mass changes, in uniform velocity motion of a body? [closed]
If a body is in motion with some constant velocity, but its mass is decreasing as it is moving forward, what will happen to its velocity?
Does it stay constant, why?
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Threshold energy for pair production from proton-electron collision
In this undergrad nuclear physics problem I am asked to find the kinetic energy threshold for an electron colliding with a still proton to create an electron-positron pair. So in short:
$$e^- + p^+ \...
- 149
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2
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Confusion on Conservation of Energy (with a spring example from Lagrangian mechanics)?
Please do correct me if I am wrong here - but it is my understanding that the following paragraph holds true:
Let $L$ be the lagrangian of a system with generalised energy $h$ and with $N$ particles, ...
- 101
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Momentum and Kinetic energy from a decay of single particle at rest into 2 particles
How can I find the kinectic energy $KE_n = E_n - m_nc^2$ and the momentum $ p_n = \frac{1}{c}\sqrt{E_n^2 - m_n^2c^4}$
From $E_n = (\frac{m_{\lambda}^2 + m_n^2 - m_p^2}{2m{_\lambda}})c^2$, which result ...
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Will the change in kinetic energy during projectile motion always zero?
Will the change in kinetic energy i.e. $\frac{1}{2}mv^2-\frac{1}{2}mu^2$ always zero in case of projectile motion
since the initial speed and final speed is the same that is $u$? If my observation is ...
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Some help in understanding energy conservation relating to special relativity
Consider the decay of particle $A$ into particles $B$ and $T$ where $T$ is the tachyon particle. The conservation of energy equation can thus be expressed as
$$m_A=\sqrt{p^2+m^2_B}-\sqrt{p^2-m^2_T}\,.$...
user161157
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3
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Is motion conserved? [closed]
In physics it is said that there is a law of 'conservation of energy'. Also there is a law of 'conservation of momentum'.
I am interested in the term or concept of 'MOTION'. I think motion is related ...
- 27
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4
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Do conserved quantities tell us more general pattern than what we are taught?
Last year I had a question in m mind that as $mv$ (momentum) and $mv^2/2$ (Kinetic energy) both are conserved then n a closed system and they are dependent on same quantities and look very similar so ...
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Kinetic energy produced in an explosion
If there is a train moving at 2 m/s with a cannon attached to it loaded with a ball, and then the ball is launched from the train, how would one find the kinetic energy produced by the explosion if ...
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Energy conservation in two-body decays?
Let's consider a generic two-body decay $A \rightarrow B + C$. In the center-of-mass frame (i.e, the rest frame of particle $A$), we know that the four-momentum of particle $A$ can be written as $p^{\...
user248824
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Calculating new velocities of $n$-dimensional particles after collision
I am working on a particle simulation where there is no gravitational force exerted on particles, they simply travel through space and, upon collision, change trajectories accordingly. There isn't a ...
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