Questions tagged [collision]

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

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How does particle size affect the elasticity of a collision between two particles?

Lets say two particles in an aerosol collide. How does the size of the particles help determine if the collision is elastic or inelastic? I am specifically referring to the following quote. It ...
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Bouncing ball physics

Do we generally ignore energy loss in kinematics when the ball ,falling under gravity , is bouncing back.Because below graph shows that Ball got the maximum velocity with which it was thrown earlier,...
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The impact and collision principle

A particle P of mass 3m is moving in a straight line with speed u on a smooth horizontal table , a second particle Q of mass 2m is moving with speed 2u in the opposite direction of P on the same ...
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Energy Loss in Inelastic Collision

If we take a tennis ball and drop it from a certain height above the ground on earth, it collides inelastically, with the maximum height it can reach reducing after each collision due to loss of ...
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Basic collision question [closed]

So I've got a problem where there are initially two identical particles of mass m. There are no other objects in the surroundings. One is traveling at $\frac{4}{5}c$ and the other is at rest. They ...
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Coefficient of restitution in special relativity

It seems that all books about special relativity only include discussion about perfectly elastic and perfectly inelastic collisions. The notion of the coefficient of restitution, $e$ in classical ...
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Does throwing a penny at a train stop the train?

If I stand in front of a train and throw a penny at it, the penny will bounce back at me. For the penny to reverse its direction, at some point its velocity must go to zero. This is the point it hits ...
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Collision of particles [closed]

I read in a book that in both elastic and inelastic collision, the interacting forces after the collision become effecitively zero, the potential energy of the system remains the same both before and ...
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How will Andromeda collide with Milky Way in spite of Hubble's law? [duplicate]

According to Edwin Hubble our Universe is expanding because he noticed that other galaxies are moving away from us. But then how Andromeda galaxy will collide with Milky Way in ~4.5 billion years, as ...
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Why conserve angular momentum about COM

In many questions involving collisions between Rigid bodies angular momentum is conserved about center of mass If bodies stick together after collision they estimate com and then conserve about ...
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Colliding elastically in lab and CM frame

Two spherical bodies of mass $m_1$ and $m_2$ are placed in gravity free space as shown. Initially, the body with mass $m_2$ is at rest and the body with mass $m_1$ approaches the other body with a ...
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To find the probability of the direction of the velocity after impact lying between given limits

I'm trying to understand Maxwell's "Illustrations of dynamical theory of gas" puts forward the argument of equal scattering probability. The area between the spherical zone is not very clear. How does ...
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Energy conservation in Elastic collision

A question from my textbook is stated below In an elastic collision The initial kinetic energy is equal to the final kinetic energy The final kinetic energy is less than the initial ...
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Uranus: The Spin

In his prog. , on the outer planets, Brian Cox stated that Uranus spins on its side because it once endured an interplanetary collision. Such a cataclysm would normally be devastating for both ...
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How to write down the collision integral for any interaction in the Boltzmann equation?

I'm studying the Boltzmann equation \begin{equation} \Big[\frac{\partial}{\partial t}+\vec{v}\cdot\nabla_{r}+\frac{1}{m}\vec{f}\cdot\nabla_{v}\Big]f(v,r,t)=\frac{df}{dt}\Bigg|_{coll} \end{equation} ...
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Producing a pair of pions

I know that two protons colliding at high energies can produce a pion $$p+p \rightarrow p+p+\pi^0$$ But is it possible for two protons to produce a pion pair? $$p+p \rightarrow p+p+\pi^{-}+\pi^{+}$$...
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Fire in my building [duplicate]

If there is a fire in a building and I am on 10th floor and I can't exit the building.Is it safe to jump out of the window with a chair and when chair is close to the ground I just jump of the chair ...
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What determines the “strength of impact” of a falling object on the ground, momentum or energy?

I am considering free falling objects that eventually hit the ground. The objects have various masses and various final (ground-impact) velocities. What should I measure the "strength of impact" ...
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Deriving expressions for momentum in relativistic elastic collision

I have the following question from D'Inverno book 'Introducing Einstein's Relativity': A particle of rest mass $m_0$, energy $e_0$, and momentum $p_0$ suffers a head on elastic collision with a ...
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Time taken to reach common velocity - collision

Say for instance I have two objects with different masses that collide in-elastically the resulting velocity will be $ v =\frac{m_1 v_1 + m_2 v_2}{m_1 + m_2}$. What I don't fully grasp is how to ...
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Are springs compressed by energy, or by momentum?

An object is headed towards a spring at a constant velocity, no external force will act upon it, except for any force applied by the spring itself after the collision. Let's say the spring is of ...
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1answer
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When a rod collides with a particle does the momentum of the centre of mass remain conserved or of the small part of rod colliding with the particle?

I have observed in many experiments on collisions involving rods of varying densities that the momentum seems to first be conserved only at the point of collision then about the centre of mass. Is my ...
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Would a relativistic collision create a black hole?

Imagine an ultra relativistic object with a very small rest mass, but an extremely high kinetic energy in our reference frame. So high that a stationary object with the same amount of energy would ...
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In which direction does the impulse acts on ball when we throw it to ground? [closed]

When we throw a ball to the ground then in which direction does the impulse acts on the ball?
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Is it momentum/force or pressure that determines the damage of an impact?

So a tiny object and a huge object that have the same mass and velocity strike a surface. Because they have the same mass and velocity, they would have the same momentum and will deliver the same ...
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When I stop my car, how much energy is transferred to the brakes as heat, and how much is transferred to earth?

Assume I'm travelling at 70mph (31.3m/s) in my car and suddenly slam on the brakes and come to a complete stop. I don't brake so hard that the tyres skid. Assuming my car has a mass of 1000kg, that's ...
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Newton law of restitution 2D

https://en.m.wikipedia.org/wiki/Coefficient_of_restitution Wikipedia States that Newton's law of restitution is valid only for one dimension collision. I understand this from the derivation, which ...
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Projectile coming to a full stop at impact versus breaking through and continuing on

In the following scenario neglect any deformation forces within materials and assume the collision is inelastic. There are no instances of rebounding of the projectile at impact. There is no flying ...
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What object emits a clear measurable sound when hit?

I'm doing an experiment asking the question: How does the degree of velocity in a collision effect the intensity of sound emitted? (this might be badly phrased/asked I'll accept suggestions to change ...
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What will happen when a cart moving on a horizontal track collides with a cart of the same mass that is at rest? [closed]

Our teacher gave us several options, but the only ones that don't violate conservation of momentum are: Cart A and Cart B move together with the same velocity Car A and Car B move with Car B having ...
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How can the motion of the brain within the skull be stopped at the moment of impact? [closed]

How can the motion of the brain within the skull be stopped or controlled at the moment an object with velocity comes in contact with it. What type of a system would this require?
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Vertically falling sphere striking a wedge and rolling without slipping

I have a question which states that a sphere of mass $m$ falls vertically and strikes a wedge of mass $M$ and inclination $\alpha$, at rest on a smooth horizontal plane. There is sufficient friction ...
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Can I calculate force in the following situation if the following information are given?

A moving car collides with a stationary car, after which they move at the same velocity. After going some distance they stop. The following information is given: mass of the 2 cars the velocity of ...
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Elastic collision

In an elastic collision, 2 processes can be said to take place as mentioned here in the accepted answer: Why does a billiard ball stop when it hits another billiard ball head on? First by the ...
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What happens if matter particle and antimatter particle both carry no charge were to collide elastically?

I read that particle carrying charge is able to interact with photon so that when electron and positron collides they may be converted into pure photons, then what about neutron-antineutron collision? ...
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Why don't objects bounce infinitely?

I'm computer programmer, and I was making a little test of my “possibilities”, so to speak, so I made a small game with sort of gravity, bouncing ball and walls around. Recently I've noticed that ...
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What kind of forces develop on a solid shape suspended in bubbly fluid? Is there a name for the study of this sort of interaction?

Let's say I have a solid shape - a sphere, a cylinder, I don't know if it matters - and I place that solid in a container of water. The forces on the shape consist of gravity and buoyancy (due to ...
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Overspeed Trip Valve Design

I want to estimate impact force generated due to collision between rotating body and stationary object. Bolt assembly is in balanced condition with the spring force and centrifugal force. As the speed ...
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Possible reactions due to antiproton-proton collisions

When an antiproton collides with a proton, then "all" reactions/channels are possible, right? Only constrained by the used energy and sure, some channels are more likely than others but in principle, ...
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Angular momentum conservation during collision

If I have a disk which is pure rolling and it strikes with a ladder, so can I conserve angular momentum about point O? I think I can because normal reaction passes through O, so torque due to it will ...
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What should be the speed of my bullet be to punch a nice round hole through a paper sheet?

If my bullet travels faster will the amount of damage done to the paper be lesser? Due to inertia of the paper can the bullet make bullet shaped holes instead of making a big hole as the speed ...
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Special Relativity; 3 Momentum Conservation

In SR, I understand you can use 4 momentum conservation, but what are the special cases where you can use 3 momentum/energy conservation? An example I have seen is with $$P_1=(M_1, 0) \\ P_2=(M_2,0) \...
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Do faster moving projectiles make larger penetration holes? [closed]

When it comes to shooting guns, a bullet of a certain size will make a certain size hole in the paper or wood target. A $.22$ bullet makes a pea size hole regardless of if its shot out of a pistol ...
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Change in momentum for gas particle collision with wall

I've attached the question as an image below as it's a graphical question. It simply states: "The diagram shows a gas particle about to collide elastically with a wall. Which diagram shows the ...
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What happens when in space a basketball flies and hits another resting basketball?

We have the following situation: In space, a basketball flies and hits another resting basketball. What happens next? a) Both balls fly in the original direction (but slightly slower) = momentum ...
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Net Force regarding Impulse and Momentum

I'm just going to preface this with: I don't know much, I've just started learning about impulse. Question: If there is a change in velocity regarding momentum $P$ then would there be a net force on ...
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140 views

Maximum scattering angle for relativistic elastic collision

In Landau Classical theory of fields, in the section of elastic collision(chapter 2, section 13), he mentions that for $m_1>m_2$, the scattering angle $\theta_i$ cannot exceed a maximum value, and ...
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Feynman's argument that at thermal equilibrium average kinetic energy of two gases are same

I had a hard time following Feynman's argument that when two different gases are present in the same box their average kinetic energy is the same at equilibrium. To quote from his book: ....Next, ...
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Collision angle relation to velocity of balls in Billiard Pool Game

I have a question about the billiard game physics. I know that in a billiard game, balls collisions are elastic and therefore the angle of the collision of two balls can easily be calculated no matter ...
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Dynamics of Event Horizons between head-on colliding non-rotating black holes [duplicate]

What happens to the event horizons of each black hole as the two identical non-rotating black holes collide head on? At a point exactly between them, is the curvature zero (do the individual ...