Questions tagged [collision]
This tag is for questions relating to collision which is the interaction between two or more bodies that results in physical contact and an exchange of momentum between the bodies involved. When it happens, kinetic energy is often exchanged between the molecules’ translational motion and their internal degrees of freedom.
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Why does a metal ball not trace back its original path if it hits a wall?
If we have a metal ball, why does it follow the law of reflection after it hits a wall? My point is that if it applies a force on the wall at an angle say 30deg below the horizontal (the wall is the ...
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How to determine particle energies in center of momentum frame? [closed]
I want to show for the following process that, except for the angle $\theta$, all momenta and energies are fixed by energy-momentum conservation.
Namely:
$$p_A=\frac{1}{2\sqrt{s}}(s+m^2_A-m^2_B\space,...
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At near light speeds, are small objects in your path a problem?
A mental exercise: A space ship is accelerating toward me from far away. As it approaches me, I can observe its acceleration. This high speed ship keeps accelerating faster toward the speed of light. ...
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Why is compton scattering inelastic?
With Compton scattering the total momentum and the total energy of the photon electron system is conserved, so it has to be ELASTIC Collision/Scattering.
But an argument is that just because the ...
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In a collision, is momentum proportional to the force that an object can apply
If object A's momentum is decreased, will it produce less force on object B upon collision, in comparison to a situation where A object had greater momentum?
If this is true, does it follow that the ...
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In an elastic collision, is conservation of energy and momentum enough to define the behavior of a system?
An example I was thinking of is two balls of equal mass M, where the first ball has an initial velocity of v_1 m/s, and the second ball has 0 velocity. The final velocities are v_2 and v_3 ...
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Deviation from law of reflection in (non-perfect) inelastic collisions
Does the law of reflection hold for balls bouncing inelastically on inclined planes?
In the above question, an answer included the following paragraph:
The law of reflection only holds if the ...
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Velocity at impact
I am a high school student and have been wondering about this for a while: When a ball is either smashed or thrown down onto the ground, does the momentary velocity become zero at the moment of ...
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Direction of momentum in a collision
In a simple perfectly elastic collision 1-D collision, with a ball of mass M_1 striking a rigid wall of mass M_2 head on,also$$M_2>>M_1,$$
then by law of conservation of momentum. $$\Delta\vec{...
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Is there a term for head-on collisions that don't seem head-on in the lab frame?
I have found that generally, you can speak of 'Head-on' collisions if they are head-on (in any frame of reference) and 'glancing', 'oblique', or 'non-head-on' collisions if they are not (the impact ...
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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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Relation between Youngs Modulus and Co-efficient Of resistitution [duplicate]
I was thinking that $Y$ (youngs modulus) should be dependent on $e$ (Co-efficient of Restitution) as COR explains the separation/approaching ratios of velocities of 2 objects colliding, The velocity ...
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Conservation of momentum and energy: what is considered to be the system?
In an inelastic collision where mechanical energy is not conserved, momentum is still conserved. Should the Earth or the ground be considered as part of the system in order to account for the ...
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Which physics is true based on different reference frames? [duplicate]
There is one movement action based on two different reference frames.
I’m moving to a fixed wall with velocity $v$ if we take the ground as a reference frame, and I hit the wall and stopped.
The ...
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Minimum energy required to behave like a turning point?
So I've managed to confuse myself.
We know if the energy equal to the potential energy then point at which the energy exceeds the potential energy it behaves like a turning point (slide 2). Usually in ...
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Direction of recoil in $B$-decay [closed]
What is the direction of recoil of product nucleus in $B$-decay? I believed it to be by intuition, opposite to the direction of emission $B$-particle but when I wrote that in my exam, it turned out to ...
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What are the exact conditions for 1D elastic collisions? Is there a list for characterizing when elastic collisions occur?
We know there are elastic, inelastic, and partially elastic collisions. In a fully elastic collision, both momentum and kinetic energy are fully conserved. However, that tells us nothing for which ...
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3D perfectly elastic collision between two points
There is a high probability, I think, that this question is a duplicate of some other question ... but to may knowledge, it hasn't been posed in this exact manner:
Assume we have 2 points, $P_1$ and $...
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How are we able to study Quantum phenomena in Particle physics using relativitity?
When we look at at a relativistic collision like compton scattering or decay of the Higgs particle, we treat the colliding particles literally as particles following a definite trajectory and ...
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How does an electron absorb the energy released during inelastic collision between a neutron and the nucleus of a hydrogen atom?
In atomic collisions,does the neutron fuse with the proton of hydrogen and release a photon which is absorbed by the electron which then gets excited to higher energy state?
Or do the neutron and ...
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How to modify kinetic gas theory to work for macroscopic particles? (2D)
For the first time I framed a question on my own when I was recently playing carrom pool with my cousin and a striking thought ran across my mind!
I was thinking if a square frame is fixed rigidly on ...
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Why can a beam of electron and not scatter with a proton to form a H atom? [duplicate]
*Consider aimimg a beam of free electrons towards an isolated free proton . When they scatter, an electron and a protons cannot combine
to produce a H-atom because
A) Energy Conservation B)without ...
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Holes in phase space because of collision potential?
Consider a gas. Now, we already know the particle's duration of a collision is very small and it immediately bounces away from there. Can these be thought of as topological holes in one's phase space ...
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Efficiency of particle accelerators
Say the SLAC linear accelerator, to perform inelastic scattering, wants to fire an electron accelerated to 0.99c the speed of light at targets of atomic nuclei.
After the collision, the resulting ...
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Is it correct to say that it is theoretically impossible for perfect rigid bodies to exist?
If perfect rigid bodies were to exist, then consider a scenario in which two rigid bodies of equal masses moving with velocities of equal magnitude but opposite in direction colliding against one ...
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Question about the energy of the gravitational waves produced by massive astrophysical objects merger
My doubt lies in the fact that gravitational waves are produced even before the merger so I kindly ask an expert to make me a clear picture of the source of energy of grav. waves before the merger and ...
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How to derive the modified Mott formula (with target recoil) using quantum field theory?
The differential cross-section of relativistic point electron off a static Coulomb potential provided by a point charge with density $\rho(\vec x)=e\delta^{(3)}(\vec x)$ is given by the Mott formula (...
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Why doesn't conservation of energy hold here while conservation of momentum does? [closed]
When trying this problem, I first used conservation of energy as follows:
$$\frac{\beta}{4D^2}+\frac{1}{2}m{v_0}^2=\frac{1}{2}m*\frac{4}{9}{v_0}^2+\frac{\beta}{x^2}$$
$$\frac{\beta}{4D^2}=\frac{1}{2}m{...
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Deep inelastic scattering remains
So I know that the process of deep inelastic scattering results in a collision of an electrons and protons in very high energies. However, I'm guessing that after the parton hadronizes, where would ...
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Maximum force during a collision
When 2 bodies collide with each other, they deform for a while. The contact force rises, reaches a maximum, then falls. It is easy to find the average force during this time if we know the duration of ...
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Is total Mechanical Energy Conserved in an inelastic collision with negligible friction?
I understand that in an inelastic collision, mechanical energy is lost to heat, sound, deformation, etc. However, if there is no friction between the two objects that collide or the two objects with ...
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Is my method here for solving this 1D 3-body collision problem correct?
I was attempting to solve a three body problem which I made up that goes like this:
The diagram shows their velocities and masses just before collision.
The coefficient of restitution between each ...
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If a vehicle with constant velocity hits me then is it correct to say that the vehicle exerted no force upon me and therefore I am unhurt?
Consider the scenario where a vehicle moving at a constant velocity collides with me and maintains it's constant velocity during the collision. What I think is that I may get hurt, which is just ...
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Why do cars rotate during a "small overlap" crash test?
I was watching a "small overlap" car crash test video and I noticed that the car tended to rotate around to the right side during the collision (see the figure below). My question is why ...
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Conservation of Momentum for collision - when shold I use the impulse?
I'm doing a problem on collision. In the previous exercises I used to use the law of conservation of momentum. Say for particle A and B, where $v_i$s are the final velocities and the $u_i$s the ...
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Looking for a physics model of a ball's bounce
For a physics project , I will try to study the deviation of a sliced tennis ball after its bounce. So I'm looking at the influence of the linear speed and the speed of rotation of a ball on its ...
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Calculating the damage done by a boxer's punch
I'm developing a VR boxing game and I'm curious about what would be the most accurate calculation to define a damage number for a boxer.
Right now I'm using Collision Response equation by putting ...
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Condition for collision [closed]
Assume we are given two particles of equal masses, with their velocity and position vectors, at some instant in time. Under what relationship of the velocity and position vectors will these masses ...
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What happens to force, impulse and time of a collision as velocity is doubled?
If an object collides with a massive wall (massive enough that it would hardly move) at velocity V, it will have force F acting for time T, giving impulse of I. If you increased the collision velocity ...
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Angular momentum decomposition in COM frame when COM rotating
Here is the question. Now I want to understand the alternative method below to solve the angular momentum. Normally in a point we can decompose the angular momentum about the point into distance ...
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Force exerted on vehicle when hitting an object [closed]
How can i calculate force that is exerted on a vehicle when it hits an object?
Vehicle speed is 40 km/h, mass is 1500kg
Object is standing still (speed is 0 km/h), object mass is 11kg.
Now this ...
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Calculating momentum change?
A 100 g ball with a speed of 5 m/s hits a wall at an angle of 45 degrees. The ball then bounces off the wall at a speed of 5m/s at an angle of 45 degrees. What is the change in the momentum of the ...
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What happens to protons AFTER deep inelastic scattering occurs?
As I understand in the deep inelastic scattering process, a collision of electron beams and protons occurs, resulting in a scattered electron. However, when the proton absorbs the virtual photon ...
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ProtoElectric Effect: How would this work?
In the 'Photoelectric Effect' setup, if I replace the light source with a 'Proton Gun', What would be the result?
I tried to search around and could shortlist a few possibilities, but am not sure if ...
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Could someone give me the explanation for this scenario?
I fixed inclined wedge. I throw a ball from height say h meters above its point of impact of the inclined plane. And lets say the inclined plane is smooth (no friction) but has a coefficient of ...
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How does dual nature of matter affect collision at the quantum level?
I have a question suppose having two fundamental particles collide which each other at the quantum scale , then what will the collision behave as
Will the particle nature be dominant and make sure to ...
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Force Problem with Punching Glove?
Consider a man with a thick padded punching glove who strikes a bag. He then strikes that same bag without a punching glove. Both punches travel at the same velocity. Which one exerts more force? ...
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What's the difference between these two 'process'?
In my text book it talks about about protons colliding: to demonstrate the idea of pair production and quark confinement.
In both scenarios two protons collide (the energies of each are not stated ...
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Why is maximal kinetic energy lost in a perfectly inelastic collision?
A perfectly inelastic collision is one where both of the colliding objects stick together and move as one.
My question is, why, of all possible combinations of final velocities that conserve momentum, ...
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Problem with two dimensional collision [closed]
I'm having it hard trying to solve this problem, i've tried but still with no certain results. The problem is this, We have an object with a triangular rectangular shape, above this object there is a ...
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