Interaction between two or more bodies that results in physical contact and an exchange of momentum between the bodies involved.

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Collision and momentum conservation principle

Consider the following problem: A ball is dropped with an angle a between its direction and the normal of the floor and bounces up with an angle b between its direction and the normal of the floor. ...
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2answers
134 views

What makes a collision superelastic?

I've seen an online definition: A collision in which potential energy is converted into kinetic energy so that the total kinetic energy of the colliding objects is greater after the collision than ...
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69 views

Dissipated Energy from Falling Object using Lagrangian [closed]

A plate of mass $M$ moves horizontally with initial speed $v$ on a frictionless table. An object of mass $m$ is dropped vertically onto it from the height $h$ and smashes. How much energy is ...
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102 views

Prove the relation between relative velocity ,momentum and energy

In Chapter 8 of F.Mandl's book Quantum field theory, during the derivation of the differential cross section, the following relation is used: $$E_1E_2v_{rel}=\sqrt{(p_1p_2)^2-m_1^2m_2^2} \,\, ,$$ ...
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56 views

Is collision in ideal gas because of physical collision or due to repulsion force

Is collision in ideal gas because of physical collision or due to repulsion force when they approach close by?
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276 views

why ions and electrons are at different temperatures in plasma?

In plasma, collision rate among ions or electrons is much larger than the collision rate between ions and electrons. why is that so?
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393 views

What causes damage, kinetic energy or momentum?

Let's assume we have 2 bullets. The first bullet has $450$ $J$ of KE and $3$ $kg.m/s$ of momentum, while the second bullet has $250$ $J$ of KE and $5$ $kg.m/s$. Now if they are both shot at ballistic ...
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240 views

Case of the mysterious bullets (taken from Mad About Physics)

"Two ideal bullets, identical in shape, size and mass, strike the same target with the same speed just before the collision. Force meters at the target register two times the force value for bullet A ...
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1answer
52 views

Dual and Multiple scattering of protons in light elements

I was wondering whether dual large angle scattering and multiple small angle scattering is of great significance in proton colision with light nuclei in comparison to heavy nuclei. For instance given ...
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125 views

Relativistic Conservation laws [closed]

Conservation of Relativistic mass and thus energy is easily proven by considering an inelastic collision of two bodies while invoking the conservation of momentum. As such the momentum law appears ...
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187 views

Why isn't jumping against a wall an elastic collision?

According to this calculator http://www.abecedarical.com/javascript/script_collision1d.html when low mass object hits high mass object it is reflected gaining opposite velocity almost the same as ...
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54 views

Indicate if objects after collision will stick

Is it possible to indicate if objects after collision will stick together knowing their properties(materials,hardness,etc)?
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47 views

Regarding luminosity monitor of particle collider

I am sorry if my question is completely wrong or foolish I would feel glad to be corrected On the wiki page for Bhabha Scattering, it is mentioned that it is used as luminosity monitor in many ...
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207 views

What factors indicates inelastic collision?

I am watching this example from Wikipedia: I am wondering what factors would indicate that the collision of 2 objects will be inelastic (I know macroscopic scale impacts are never perfectly ...
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1answer
136 views

What is the rebound angle of a circle striking a concave surface?

First, pardons to all because I don't have a physics background and I'm probably using laymans terms. What is the rebound angle of a circle striking a concave surface? Assume the simplest case: ...
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1answer
69 views

Examples of evolving networks in physics [closed]

I'm a master student working on networks analysis in general. A network is something that has nodes and there are links between the nodes. Nodes and links could have attributes. An evolving network is ...
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1answer
131 views

Rigid body collision, 3 circles in contact

I'm working on a 2d physics simulation. It's a continuous time simulation, that is, it uses swept shapes over the time-frame and geometrical/vector 'analysis' to determine most immediate time of ...
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1answer
157 views

Is the center of mass in general relativity equal to the center of mass in newtonian gravity?

Consider 2 point masses $A,B$ a distance $d$ away from eachother without velocity or rotation spin. Is the center of mass in general relativity equal to the center of mass in newtonian gravity ? In ...
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61 views

Lifetime of Positron and its existence

Since we know in condensed matter the lifetime of positron is about 10^-10 seconds, how do we collide positrons with electrons? How many positrons were there during the LEP experiment? I know ...
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1answer
472 views

Velocity after inelastic collision between bullet and block [closed]

The following is the problem that I am working on. A bullet of $.01\: \mathrm{kg}$ is shot into a block of mass $.89\: \mathrm{kg}$ that is hanging from the ceiling. After the bullet has been ...
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3answers
523 views

Determine resultant velocity of an elastic particle-particle collision in 3d space

So I have two particles that have collided in 3 dimensional space. I want the particles to rebound off of each other in an elastic manner. How do I determine the resultant velocity vector if I know: ...
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1answer
1k views

Calculating a 2D collision between two perfectly circular disks [duplicate]

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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431 views

Explain these graphs of rotation and velocity of pucks on air hockey board

I've been tasked to do a simple experiment on the elasticity of collisions. For this experiment I used two "pucks" (very light circular metal pieces of certain height but hollow) and a table that ...
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4k views

Elastic Collision with objects of the same mass

I understand this is a homework problem. I don't expect anyone to do my homework for me, but help me understand what I am doing wrong. The problem goes: Two shuffleboard disks of equal mass, one ...
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156 views

Where can I find the equations for “quasi” elastic collisions?

Yes, you all talk about neutrinos and spins, but I came out with this basic s**t :D All of us learnt the basic equations of collisions, elastic (everything bounces and energy remains the same), or ...
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Collision symmetry and measuring the asymmetry in the Drell-Yan process

I saw a talk the other day about an asymmetry in the Drell-Yan process caused by CP-violation: Apparently one way this can be measured (ATLAS is doing this) is to collide protons and observe the ...
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4answers
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Car Crash Scenario [closed]

Two vehicles travelling at 80mph in the same direction. Vehicles are directly behind each other. 12 meter distance between them. Front door of car in front rips of and hits the front window of the ...
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3answers
92 views

Trajectory of rolling billiard ball after collision with another billiard ball with same mass

So, according to this article http://www.real-world-physics-problems.com/physics-of-billiards.html , the trajectory of white (cue) ball is always perpendicular to the line connecting center of ball ...
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momentum equation to find velocity of solid particle after collision [closed]

If a particle collides with a liquid drop, particle might penetrate into drop and so the velocity of particle reduces. i.e. a sudden change in particle velocity happens right at the collision moment, ...
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41 views

Inelastic Collision and Energy

How is is possible for momentum to be conserved and for KE to not be conserved? Momentum is related to velocity and velocity is related to KE, therefore if KE was lost, how can the system have the ...
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50 views

How to explain the momentum exchange of two solid particles collision at molecular scale?

Here is my question: assume two solid sphere collided to each other in vacuum, at macroscopic, it can be explain by Newton's law. But at molecular scale, does the surface atoms touch to each other or ...
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64 views

Relating to Inelastic Collisions

There is a very simple equation for an inelastic collision but it really only applies to 2d scenarios: $$v = \frac{(m_1 u_1 + m_2 u_2)}{(m_1+m_2)}$$ What would be the equation for an inelastic ...
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25 views

A particle collides with another particle in an (infinitesimally long?) elastic collision, what is the resultant force?

When an object collides with another object in an elastic collision, the first object exerts a force on the second object (and vice versa); how do you calculate the force that the object experiences? ...
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86 views

Throwing a baseball against the back of a car [closed]

We, some fellow students and I, are trying to figure out what to. But we simply do not know which formula to use at question a. We found the following: $\Delta P=(2mv_{ball,i}M)/(m+M)$ Could someone ...
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200 views

Work-Energy theorem vs conservation of mechanical energy? [closed]

Bodies A and B are moving in the same direction in a straight line with constant velocities on a frictionless surface. the mass and the velocity of A are: 2kg and 10m/s. The mass and the velocity ...
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66 views

Modeling a collision phenomenon [closed]

I have a single water droplet (d~3 mm) which collides with a solid particle (d~2 mm) with a relative velocity around 10 m/s. After collision, particle rips the droplet and goes through it. Therefore, ...
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0answers
53 views

Elastic Collision [closed]

A cube has a side length of 20 cm. An atom in the gas moves around the cube as shown. It continually bounces off the four lateral walls of the cube. The atom has a mass of 6.6×10−27 kg. Because of the ...
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42 views

Books on collision probability and collision processes

Are there any books specifically on collision processes between atoms and molecules and collision probability? I would like to get an overview of the factors that determine collision probability ...
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85 views

Collision Resolution System Adding Velocity Into System

In my 2-dimensional physics simulation, I have a rectangular rigid body 'a' with infinite mass (the floor), and a rectangular rigid body 'b' with finite mass above it turned at a slight angle. When ...
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1answer
64 views

Throwing ball against oily/slippery wall

I would like to know whether a ball bounces back normally if you throw it against an oily wall. Like a wall watered down with oil. Basically I want to know if it will actually slip before bouncing ...
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2answers
132 views

Bullet entering target [duplicate]

I've been given this question: A bullet entering a target with an initial velocity of $ u $ loses $\frac {u}{n}$ of its velocity after penetrating a distance $ a $ into the target; how much ...
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114 views

2d pool collision with rotational motion

I'm trying to calculate two 2d disks' collision with rotational motion. The collision is perfectly elastic: the sum of translational and rotational energy is conserved. In the instant of the collision ...
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0answers
70 views

Which body position causes the least amount of negative acceleration? [closed]

Let's say you are in the air 500 meters above flat land and you have no parachute. Which pose - forming a sphere or spreading all extremities to make yourself as wide as possible or other - is the ...
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1answer
134 views

How to apply conservation of angular momentum with a shock? [closed]

I got this tricky question, need help. A uniform rod of mass $M$ and length $L$ is attached to an axis at its top, a bullet with mass $m$ traveling at speed $U$ (horizontal) hits the rod at $2L/3$ ...
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283 views

Electron and photon collision

So electron moving left ($v_{initial}=0.8c$) collides into photon going right. After the collision electron is moving to right ($v_{after}=0.6c$) and the photon is moving to left. What is the ...
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134 views

Asteroid collision debris calculation

I wonder how to determine the directions, in which the collision debris is launched when 2 asteroids collide. I am aware of: m1*v1 + m2*v2 = m*v = m3*v3 + m4*v4 + m5*v5 + ... and this works just fine ...
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157 views

what happens during collision at molecular level?

When two massive bodies collide we treat them simply by their mass interactions with momentum and energy conservations. Down at the molecular level it must be more like a field particle collision for ...
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95 views

Nucleon-nucleon collision density

Can someone help me derive expression for nucleon-nucleon collision density as a function of transverse plane coordinates (ultra-relativistic heavy ion collisions) using Wood-Saxon nuclear densities( ...
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45 views

Decrease in Intensity [closed]

A beam of particles pass through a target made of thin foil of a very small thickness $\Delta x$ having $N$ particles per unit volume. Let the collision cross section be $\sigma$ . If the intensity of ...
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39 views

Trouble evaluating an integral arising from particle collision

Assume we have two charged particles colliding. He have particle 1 with mass $m_1$, charge $Z_1 \cdot e$ which travels in $x$-Direction passing by a STATIONARY particle 2 (mass $m_2$, charge $Z_2 ...