The collision tag has no wiki summary.
11
votes
1answer
104 views
Mars just collided with Earth! A question of eccentricity
One of the standard theories behind the formation of our Moon is the giant impact hypothesis, according to which Earth was struck by a Mars-sized body (about $10\%$ the mass of Earth) early in its ...
-1
votes
0answers
37 views
If Galileo had an electronic scale [closed]
If Galileo had an electronic scale, capable of absorbing the collision (without breaking) of 1 Kg sphere dropped from the top of Pisa tower what would had been the maximum measurement registered after ...
21
votes
5answers
1k views
Is a proton collision (collisions like in the LHC) visible to the human eye?
I was curious if a proton collision is visible to the human eye.
(This might sound like a really basic question and forgive me if it is. I am very inexperienced in Physics and just wanted an answer ...
1
vote
1answer
47 views
Matter and anti-matter collision energy problem
From Beyond Einstein, by Michio Kaku and Jennifer Thompson, Chapter 13, Antimatter :
Dirac, also focused on the fact that Einstein's equation $E=mc^2$ wasn't totally true. (Einstein was aware that ...
-4
votes
3answers
79 views
Safest place to sit in the car [closed]
I have to sit in a car which has normal seats in the front, and lounge type chairs at the back, with seatbelts only in the front. The driver drives fast, and I think I may have an accident. So, ...
0
votes
1answer
54 views
Bouncing ball simulation computer science
In my Computer science class I was given a problem where I have to simulate a bouncing ball using "real physics". I have been trying to find a equation that will simulate the height of the bounce ...
0
votes
1answer
47 views
Something about collision [closed]
A sphere P of mass m, travelling with speed $u$, makes a head-on collision with a stationary sphere Q also of mass m. After the collision, the velocities of P and Q are $v_1$ and $v_2$ ...
3
votes
1answer
63 views
Can a linear momentum generate angular momentum at collision?
I'm trying to get the facts straight here.
Suppose I'm throwing a ball with no angular momentum. It collides with the ground and Newton's third law tells us that a force opposite to the gravity will ...
1
vote
2answers
74 views
Collision between a photon and an electron
Looking through this AP Physics question, I was struck by how the 'collision' between a photon and electron looks so much like a macroscopic collision. Is this even physically possible?
Look at the ...
0
votes
2answers
48 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 ...
11
votes
2answers
199 views
What happens in electron-electron collisions?
What are the results of high energy electron electron collisions? Are other particles created?
5
votes
0answers
86 views
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 ...
0
votes
2answers
54 views
Simple conservation of momentum and frame of reference problem
I'm making a very simple physics engine based on momentum, and I'm solving what response to use for a collision from each involved object's frame of reference. However, something about how I'm ...
1
vote
0answers
56 views
Matrix element approximation
In the formula for the decay width of $\Upsilon(4S)$ to B-mesons from $\text{e}^+\text{e}^-$ collisions:
$$\Gamma_{\Upsilon(4S)\to B\bar{B}}=\frac{\left|\underline{P}_B \right|}{8\pi ...
3
votes
1answer
82 views
Angular momentum after elastic collision
If two balls collide (elastically) and there is no friction between them, will their angular momentum change after the collision?
2
votes
1answer
43 views
Finding the coffecient of restitution
A ball moving with velocity $1 \hat i \ ms^{-1}$ and collides with a friction less wall, afetr collision the velocity of ball becomes $1/2 \hat j \ ms^{-1}$. Find the coefficient of restitution ...
0
votes
2answers
188 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 ...
3
votes
1answer
200 views
Firing machine question
Suppose we have a firing machine on a frictionless surface at point $x=0$. It fires a bullet of mass $m$ every $T$ seconds. Each bullet has the same constant velocity $v_0$. There's a body of mass ...
0
votes
0answers
16 views
Collision response between a mass and a line attached to two masses [closed]
I'm currently in the making of a small simulation program and, as I am very new to physics, I am struggling with what seems to be a simple 2D collision response problem.
I spent quite some time ...
0
votes
0answers
37 views
Mechanics: collision & rotation [closed]
A rod AB of mass M and length L is lying on a horizontal friction less surface. A particle of mass m traveling along the surface hits end A of the rod with a velocity 'v' in a direction perpendicular ...
1
vote
0answers
14 views
How to write down the detailed balance (microreversed) amplitude
I know that time-reversal of a reaction and the detailed balance (microreversed, or reciprocal) reaction are different. Textbooks on scattering theory explain how to relate the S-matrix elements of a ...
0
votes
1answer
60 views
Do particles in the solar core travel at the same speed as they would in vacuum?
I just read the Wikipedia article on the Sun. The section on Solar Core states
It has a density of up to 150 g/cm3[47][48] (about 150 times the density of water)
Do the particles (atomic, and ...
0
votes
0answers
44 views
Inelastic relativistic collision [closed]
I have to solve the following problem:
A particle of rest mass, $m_1$, and velocity $v_1$ collides with a stationary particle of mass $m_2$. Find the rest mass $m$ and velocity $v$ of the resultant ...
2
votes
2answers
130 views
Elastic collision and spring
Bodies $A$ and $B$ are moving in the same direction in a straight line with a constant velocities on a frictionless surface. The mass and the velocity of $A$ are $2 \text{kg}$ and $10 \text{m/s}$. ...
0
votes
1answer
74 views
Newton's second law?
$F=ma$. A car strikes a wall at 60 mph. Its acceleration is zero at the time. The force of the car against the wall or vice versa is? To look at the car the force is not zero. Please explain.
2
votes
0answers
120 views
Elastic collision of rotating bodies
How would you explain in detail elastic collision of two rotating bodies to someone with basic understanding of classical mechanics?
I'm writing simple physics engine, but now only simulating ...
0
votes
0answers
103 views
Scattering and partial wave analysis for cross section [closed]
Problem
Given the central potential:
$V(r)=-\frac{\hbar^2}{m a^2}\frac{1}{\cosh({r\over a})}$
and given that we know the solution to the following ODE
$\frac{d^2 y}{dx^2}+k^2 ...
0
votes
2answers
56 views
Minimum $E$ of $p\bar{p}$-collision for $q\bar{q}$ pair with mass $m_q$
I am currently working out the energy required to create a particle anti-particle pair from a collision of a proton travelling along the x-direction with an anti-proton which is at rest. The particle ...
3
votes
1answer
99 views
Why do we hear a higher pitched sound out of water when we hit two stones against each other in the water?
The observer is outside the water; the stones are underwater (say, 1 m below surface, if that matters). This produces a higher pitched sound for the observer than when both the observer and the stones ...
4
votes
2answers
113 views
Best shape to reduce the splash of a droplet?
Our coffee machine catches the last couple of droplets, after your cup is removed on a shape to reduce plash of the coffee droplets.
These shapes are placed inside the spill reservoir.
The shape ...
1
vote
3answers
130 views
Couldn't we measure electrons with good enough technology? [duplicate]
I am a bit confused about the Heisenberg's Uncertainty Principle - just read about it in How to Teach Physics to Your Dog, by Chad Orzel. He states that the reason electrons can't be measured is ...
0
votes
2answers
645 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
202 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 ...
1
vote
1answer
56 views
Mean value of the force in a collision problem
I have the following problem:
A point with mass $m$ and speed $v$ collides with a fixed obstacle and penetrates it, stopping in a space $\Delta x$. Calculate $\Delta t $.
I understand the way my ...
2
votes
2answers
311 views
Small car colliding with large truck
A small car collides with a large truck. Why do both vehicles experience the same magnitude of force? Wouldn't the large vehicle experience less force than the small one?
1
vote
1answer
80 views
How to get the new direction of 2 disks colliding?
I'm developing a 2D game including collisions between many disks. I would like to know how I can get the angle corresponding to the new direction of each disk.
For every disk I have this information ...
15
votes
6answers
1k views
What would happen if Large Hadron Collider would collide electrons?
After some reading about the Large Hadron Collider and it's very
impressive instruments to detect and investigate the collision results,
there is a remaining question.
What would happen if the ...
0
votes
0answers
56 views
Continuum mechanics and effects of stress
Going to word this question a bit more straightforward than I may have before. Also, I'm trying to use baby formulas so I can grasp exactly what's going on.
Object A has an elasticity of ...
3
votes
2answers
198 views
Spinning spheres colliding
In an ideal environment with no friction, in a vacuum, what happens to the velocity of the spin of two spheres spinning in perfect parity at two different velocities when they come into contact?
4
votes
1answer
162 views
What is the result of a classical collision between THREE point particles at the same precise instant?
Classical Mechanics is said to be deterministic, a statement that nearly always is followed by that quote from Laplace, something like
If at one time, one knew the positions and velocities of all ...
2
votes
3answers
180 views
Simple elastic collision
If a particle with mass $m$ collides with a wall at right angles, and the collision is perfectly elastic. The particle hits the wall at $v\ ms^{-1}$. There is no friction or gravity.
So the particle ...
2
votes
1answer
115 views
Swords, impacts and elasticity for a noob
So I'm a game developer and I'm trying to understand some (extremely) basic facts of impact mechanics. I had read something entitled Dynamics of Hand-Held Impact Weapons, but it was a bit too ...
0
votes
1answer
294 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 ...
-1
votes
3answers
181 views
Classical mechanics and the speed of a train-mosquito collision, when perfectly rigid bodies
This is all under the assumption that they are perfectly rigid bodies:
A train is moving at 300m/s.
A mosquito is moving directly towards it, head-on, at 4m/s.
When the mosquito and the train ...
0
votes
1answer
98 views
How to get energy of collision if you know force of gravity of an object($m \rightarrow F=mg$)?
How to get energy of collision if you know force of gravity of an object($m \rightarrow F=mg$)?
You get energy of collision by kinetic energy $E_k= \frac{1}{2}mv^2$, but if you use just force of ...
14
votes
6answers
3k views
Is two cars colliding at 50mph the same as one car colliding into a wall at 100 mph?
I was watching a youtube video the other day where an economist said that he challenged his physics professor on this question back when he was in school. His professor said each scenario is the same, ...
0
votes
1answer
333 views
Elastic Collision And Momentum
The question I am working on is, "Two blocks are free to slide along the friction-less wooden track shown below. The block of mass $m_1 = 4.98~kg$ is released from the position shown, at height $h = ...
0
votes
1answer
119 views
Analysis of the impulse of 2 colliding carts under the effect of magnetic repulsion
Hi there! I have a question about an experiment that was conducted. It is related to momentum.
2 carts were put on a track on opposite sides. They were then propelled towards one another at ...
1
vote
1answer
154 views
Momentum And A Car Collision
I am studying an example problem, concerning the very topic mentioned in the title. In this example problem, a car has a head-on collision with the wall; the initial and final velocity are known, as ...
0
votes
1answer
69 views
A Decrease In Momentum?
The specifics of a question I am working on are, "After a 0.280-kg rubber ball is dropped from a height of 1.80 m, it bounces off a concrete floor and rebounds to a height of 1.45 m."
Why doesn't the ...
