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

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6
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7answers
490 views

Hit by two cars with same momentum but different mass. Which is more painful?

Suppose they have the same contact area with you. The term "painful" is a bit ambiguous. Let me ask in another way: Two cars with same momentum but different masses are going to hit a wall. You ...
5
votes
8answers
11k views

How can momentum but not energy be conserved in an inelastic collision?

In inelastic collisions, kinetic energy changes, so the velocities of the objects also change. So how is momentum conserved in inelastic collisions?
3
votes
2answers
135 views

Physical Role of Batter in Baseball

Physically, what is the role of a batter in baseball? My question is inspired by How does the speed of an incoming pitch affect the speed of a baseball after it's hit? The answer to that question, ...
1
vote
2answers
9k views

Perfect elastic collision and velocity transfer

So my teacher told me that when you have two identical balls in a perfectly elastic collision, the first ball A will collide with B and afterwards A will stop and B continue. Why is this? Doesn't ...
2
votes
1answer
104 views

Finding direction of a ball after collision in cartesian coordinate system [closed]

In elastic collision of ball to wall along x axis m*Vix=m*Vfx as velocity of wall is 0 before and after collision thus Vix=Vfx ......eq(1) Kinetic Energy is conserved so m*Vi2 = m*Vf2 (Vix2 + ...
2
votes
5answers
91 views

Doubt in collision

If a ball under the influence of gravity falls straight down from a height $h$, collides elastically with the floor, at the instant of collision, what forces does it experience? Shouldn't the ...
4
votes
2answers
175 views

Can computers accurately model all of the details (to the subatomic level) of macro objects in collisions?

Frequently when trying to solve cosmology questions physicists turn to computer simulations of the universe (albeit massively simplified) in order to verify or disprove their hypotheses. This got me ...
5
votes
4answers
768 views

Physics Paradox about Newtons Second Law $F=ma$

I randomly thought of this- I'm surprised it took me so long to think of it, and I'm SURE I'm making a simple oversight of something completely trivial, but here it goes. (Im only in high school ...
0
votes
2answers
10k views

Calculating force of impact

Since $\text{force = mass}\times\text{acceleration}$, is it right to say that an object traveling at a high constant velocity (zero acceleration), exerts zero force upon impact with a stationary ...
0
votes
1answer
47 views

Impulse on adjacent objects

Let's say two objects are sitting adjacent (in contact) to each other. If we start pushing one of them, we know that both the objects move, remaining in contact to each other. But let's now consider ...
2
votes
2answers
360 views

Why can't collisions be elastic?

I understand that in inelastic collisions thermal energy is given out, but why does that happen? Why can't they simply rebound without giving off energy? Also, why in some collisions more heat is ...
7
votes
3answers
1k views

What determines whether a pool ball will bouce backwards after colliding with another pool ball?

I'm no knowledgeable pool player, but I've noticed that sometimes when the cue ball hits another pool ball, they roll together; and sometimes the cue ball bounces back. And I have a very, very rough ...
2
votes
4answers
216 views

How to calculate a collision which is partly elastic and partly inelastic?

(For the purpose of this question, "calculating a collision" means: given the velocities and masses of two objects in a collision, figuring out the new velocities of both objects after the collision). ...
1
vote
1answer
36 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 ...
1
vote
1answer
44 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 ...
1
vote
2answers
111 views

Why is scattering vector $\vec{q}$ called vector of 'momentum transfer'?

In the world of scattering the angle at which you detect the scattered radiation is known as $q$, where $$ \vec{q} = \frac{4\pi\eta}{\lambda}\sin(\theta/2) $$ I read in a lot of books that this is ...
2
votes
3answers
463 views

Conservation of 4-momentum in special relativity

I understand that the inner product of two 4-vectors is conserved under the Lorentz transformations, so that the absolute value of the four momentum is the same in any reference frame. This is what I ...
2
votes
1answer
57 views

Collision of light waves & matter

When light or electromagnetic wave hits an obstacle, what happens? Are the reactions times always negligible? By reaction I mean all that happens after the hit like reflection for example.
1
vote
1answer
95 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 ...
0
votes
1answer
42 views

Velocity change of objects

Is it possible for small object (small mass, let's say bullet) to hit large object (big mass, let's say rock) and still move forward (or stop) instead of being reflected (let's say objects don't crush ...
0
votes
2answers
158 views

Calculating velocity change after impact?

Let's say there is no gravity here and objects won't crush. We have 2 rocks with $m=10\text{ kg}$. First rock has velocity $v_1=0\text{ m/s}$ and second $v_2=10\text{ m/s}$ (flying in leftward ...
5
votes
4answers
989 views

How to tell if the collision is elastic or inelastic?

I'm a programmer and a game developer, not a mathematician or a physicist. So please go easy on the math :) I know two things: How to find the new velocities of two objects after an elastic ...
0
votes
2answers
105 views

Ballistic Pendulum Demo Problem

I have a question about the following problem: I got the solution $v=\frac{M+m}{m} \sqrt{2gh}$. But my real question is in the following picture: In the above slide, how can you derive ...
4
votes
0answers
152 views

Baryonic density in collision experiments

Does anyone know any way of estimating the net baryon density in collision experiments, e.g. in LHC, RHIC, or the upcoming ones at GSI-FAIR? I have comes across many hand-waving arguments, sample - ...
1
vote
1answer
75 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: ...
0
votes
1answer
33 views

Collision of a heavy charged particle with an electron at rest - Deduction

When I was studying Nuclear Physics I saw this formula about interaction of radiation with matter. The book mentioned that when considering a elastic collision of a heavy charged particle of mass $M$ ...
4
votes
1answer
53 views

How does a (near) elastic collision work at a microscopic level?

Suppose a large mass $M$ travelling at $v$ impacts a small stationary mass $m$, then following through the elastic collisions from high school, we get that the smaller mass can exit the collision ...
2
votes
1answer
105 views

What would happen if two entangled particles collided?

Does that is even possible? I have almost zero knowledge in quantum physics, it is just a curiosity that popped in my mind.
8
votes
3answers
390 views

Formalism to deal with discontinuous potentials in classical mechanics (hard wall, hard spheres)

It seems to me that Hamiltonian formalism does not suit well for problems involving instantaneous change of momentum, like particle collisions with hard wall or hard sphere gas model. At least I could ...
0
votes
2answers
76 views

Where did the energy of the charge go?

Suppose there is a positron and an electron, and they both collide, and we get $E=2mc^2$ of energy from the collision. Now, the charge also got vanished. Now suppose, I create neutrinos from the ...
1
vote
1answer
54 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 ...
0
votes
2answers
37 views

Capturing Energy from a Positron-Electron Collision

According to the book Physics of the Impossible, the catastrophic collision between a electron and a positron yields an output of 1.02 MeV. Assuming you have an isotope like $^{22}\text{Na}$, which is ...
1
vote
1answer
58 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 ...
-1
votes
1answer
48 views

Initial velocities of a collision [closed]

This is the question: A car of mass 900 kg and a van of mass 1300 kg collide at a crossroads. Investigation into the collision discloses that the car was travelling south east and that the van was ...
2
votes
2answers
274 views

What is the relative speed of two near-light speed particles headed towards each other?

I understand that nothing can move faster than light due to time dilation. I want to build upon my understanding of Einstein's theory of Special Relativity, so I came up with this hypothetical problem ...
1
vote
2answers
121 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 ...
0
votes
1answer
103 views

Relative Velocities and Conservation of Kinetic Energy

An object of mass m moves with velocity $v$ towards a stationary object of same mass. Impact is an elastic collision. $v_1$ is the velocity after impact of the mass originally moving $v_2$ is the ...
0
votes
1answer
188 views

Bullet hits block. Show that linear momentum is not conserved [closed]

"..." First, we will familiarize us with a collision between a homogeneous beam of length, $L$, mass $M$ attached with a frictionless hinge in point $O$ at one of the endpoints of the beam. The ...
3
votes
3answers
169 views

How is angular momentum conserved if a bullet hits a wheel?

Suppose my system involves: 1) A mounted wheel with some outward flap 2) A bullet already in motion Initially the net angular momentum is 0 and the net kinetic energy is just that of the speeding ...
0
votes
0answers
74 views

Transfer Equation between two oscillating pendulum collision

How to model the energy transfer equation between two oscilators colliding? For example two pendulum oscilating at frequency $f_1$ and $f_2$ and they transfer energy during colision.
2
votes
0answers
107 views

Kinematics and Motion [closed]

If a body loses half of its velocity on penetrating 3cm in a wooden block, then how much will it penetrate more before coming to rest? How does answer come out to be 1cm?
15
votes
3answers
1k views

What happens in a car crash?

My mom and I were in a car accident. We are ok, but I want to know how fast the car that hit us was going. We were stopped at a light. The car that hit us from behind was a big GMC SUV. Our car was a ...
8
votes
3answers
951 views

Number of planks required to stop the bullet [closed]

A bullet looses (1/n)th of its velocity passing through one plank. The number of such planks that are required to stop the bullet can be? Logically, to me the answer seems to be infinity, as always a ...
0
votes
1answer
121 views

Vibration transmission using spring and damper model [closed]

I want to simulate the vibration transmission between two colliding objects. I use a Finite Element Model to simulate the vibration on each object, but I haven't found any good mathematical model to ...
2
votes
0answers
62 views

Relativity addition and signs

I have just covered a very brief module on special relativity as a part of my physics course. I have also done some extra reading mostly; Morrin's Classical Mechanics. While I found the book really ...
0
votes
0answers
39 views

Collision between 2d circle and flat surface

First of all I want to preface this post by saying that I am absolutely terrible at maths, my level of geometry equals being able to discern a circle from a rectangle but that's about it, as for ...
0
votes
0answers
21 views

If two objects collide, will the collision force be twice as big as the original force? [duplicate]

Say, if we have two trucks travelling towards eachother at 60m/s, and those two trucks carry the same payload, and are the same model (aka they're exactly the same), will the collision force be as if ...
1
vote
0answers
111 views

Collision of Discs and Snooker Kicks

I woke up this morning thinking about spinning discs. Could someone verify whether my reasoning below is correct? Problem 1 Suppose have two identical uniform discs constrained to move in a plane. ...
0
votes
1answer
105 views

Angular momentum of two rotating spheres

I am trying to calculate an instantaneous merger of two rotating spheres into one. Two spheres each rotating around their own axis of rotation (which are generally not aligned) and moving relative to ...