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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144 views

Perpendicular Elastic Collision (different masses, different velocities)

I'm stuck on a mechanics problem and I can't make any headway past momentum and kinetic energy being conserved. Here is the problem: Two hover cars are approaching an intersection from ...
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259 views

Nuclear reaction: creation of deuterium

A proton p collides with a neutron(at rest) n at relatively low-energies and creates a 'deuterium-core' d: p+n->d+γ Find the wavelength for the photon as a function of the proton's momentum and the ...
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24 views

Two dimensional elastic collisions with varying angle of incident

If in an elastic collision I know all initial values and that mass for each object remains constant throughout the collision (but different from one another) how can I determine their final velocity ...
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1answer
150 views

Definition of energy

What is the definition of energy $E$ given a dispersion relation $\omega=\omega(k)$ where $k=|\vec k|$ and $\omega$ is not necessarily linearly proportional to $k$? What about momentum $\vec p$? This ...
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159 views

Calculating a 2D collision between two perfectly circular disks

Assume I have two disks, $p_1$ and $p_2$, of radius $r$, with their own velocities (preferably in $(x,y)$ form, but $(m, \theta)$ works too) and masses (unit-less, but same unit) collide in two ...
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272 views

Kinetic energy in the center of mass

In a collision of a particle of mass $m_1$ moving with speed $v_1$ with a stationary particle of mass $m_2$ not all the original kinetic energy can be converted into heat or internal energy. what ...
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1answer
158 views

Deceleration of Vehicle off pavement

How would I calculate the deceleration of a vehicle (ATV), wheels locked, on dirt? How long would it take to halt? How fast is it decelerating? I used this calculator, but it seems incorrect for a ...
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How multiple objects in contact are resolved in an inelastic collision, when edge normals don't “line up”

In a case I understand, let's say I have an object A moving at velocity V toward 3 objects in contact B, C, and D: The momentum of A is the mass of A times its velocity. To figure out how the ...
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38 views

Best current bounds on nonconservation of momentum?

It's not straightforward to test conservation of momentum experimentally, and many experiments that seem like tests really aren't. For example, in a Newtonian system of identical particles that ...
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135 views

Early stages of a computational model for object movement charting

We would like to build a computational model capable of accurately predicting the position of any object inside a chamber at any given time. Inside the model we would have a number of smaller ...
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0answers
251 views

kinetic energy in collisions

We were hoping you could help us understand collision energy. Vehicle A is driving West at 35mph and weighs 1437kg. Vehicle B is driving North at 35 mph and weighs 1882kg. Vehicle B crashes into the ...
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17 views

How do I find the force from drop shock using material properties?

I am dropping a cylindrical cast iron bar with a know elastic modulus and poisson's ratio, $E_{1}$ and $v_{1}$, onto a flat beam of elastic modulus, $E_{2}$ and $v_{2}$ so there is tangential drop ...
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about wavefunction and vector entries

I am beginer of physics and I am studying some very fundamental idea of quantum mechanics by myself. In the introducing book I am reading, there is an example to show a particle diffraced by a slit or ...
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0answers
37 views

Need help with relativistic dynamics

I understand the concept, but I'm having a hard time applying the consequences of conservation (energy/momentum). For example: A proton with kinetic energy 437 MeV hits a proton at rest elastically ...
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0answers
247 views

Error Analysis, Change in momentum, Kinetic Energy

If momentum of an object is increased by 10%,then its kinetic energy will be increased by? Well, I don't need the solution logically by calculating the change in Kinetic Energy etc, but my question ...
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0answers
34 views

Does the direction of a rocket relative to an orbiting mass reduce the orbiting mass' orbital velocity?

Does a rocket taking off in the same direction of an orbiting mass (asteroid to planetary size) reduce the mass' orbital velocity versus the same rocket taking off in the opposite direction of the ...
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81 views

Physics behind 2 different wall kicks

I'm looking at a situation where a sprinter starts at some distance x from a wall. The goal is to sprint to the wall, hit it, and get back to the start as quickly as possible. There are two ways ...