Questions tagged [momentum]
In introductory mechanics, the momentum of a particle is its mass times its velocity. In electrodynamics, the momentum of a field is proportional to the cross-product of the electric field with the magnetic field. In special relativity, momentum is generalized to four-momentum.
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Energy and momentum conservation for photon absorption [duplicate]
As an undergrad physics student, I am pondering on this question.
If an (2 level) atom absorbs a single resonant photon, the energy of electronic state increases by $\hbar \omega$. At the same time ...
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Momentum of light in anisotropic media
This question is related to the Abraham-Minkowski controversy that has already been discussed extensively here and in the research community. But I want to ask about an aspect of this momentum ...
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Kinetic Energy change in particle to wall collision [closed]
The Question
A particle of mass m is moving in the +x direction with a speed v. It is
approaching a massive wall which is also moving in the +x direction, but
with a speed u < v (see figure)
The ...
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With two balls connected to a string find minimum upward velocity that can be given to one of the balls such that the other leaves the ground
The exact question is given below:
Two identical small balls A and B each of mass m connected by a light inextensible cord of length l are placed on a frictionless horizontal floor. With what ...
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Impulse of two different objects
I was running over a question,
A collision occurs between particles A and B which are moving in opposite directions in the same straight line. The impulse on each particle in the collision is 2N.s, ...
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Conservation of momentum of airplane in runway
On exercise 4.6 from Klepper's Book "Intro do mechanics" there is a plane on a landing lane. It has its engine off but is braking with force $F_b$. Also, it is attachted to a sandbag that ...
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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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Would a gauss rifle based on generated magnetic fields have any kickback?
In the case of currently developing Gauss rifles, in which a slug is pulled down a line of electromagnets, facilitated by a micro-controller to achieve great speed in managing the switching of the ...
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Idealized Newton's cradle
I was wondering about the conditions for an ideal newtons cradle.
Under regular circumstances, the collisions are inelastic and a newton's cradle dissipates energy in various forms like heat, friction,...
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Why is it less shocking to cross the bump with just one wheel? [closed]
Difference between 'go over speed bump with one side' and 'both sides at the same time'
I asked a similar question previously and received an excellent answer stating that when going ...
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Example on impulse
A rubber ball of mass $50g$ falls from a height of $1m$ and rebounds to a height of $0.5m$. Find the impulse and the average force between the ball and the ground if the time for which they are in ...
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Is the Potential Energy just a bookkeeping device?
It is said that if the space is homogeneous then momentum is conserved. But I've been thinking in the following situation:
Consider a parallel plates capacitor. In between the plates there is a ...
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Why the $E$ of the time component 4-momentum is the total energy and not another?
The time component of the 4-momentum is $E/c$, and I saw that it is the "total energy" and from here we can derive the formula $E^2 = (pc)^2 + m^2c^4$.
But how do you know that $E$ is the total ...
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Apparent violation of Newton's Third Law in relativistic force transformation
In special relativity, we know that, relativistic force is defined as F = dp/dt, where p = γmv.
For forces perpendicular to the direction of relative motion, force transforms as F' = γF.
Consider two ...
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Direction of impulse
My textbook has the following problem:
A batsman deflects a ball by an angle of 45° without changing the initial speed which is equal to 54 km/h. What is the impulse imparted to the ball? (Mass of ...
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