The collision tag has no wiki summary.
-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 ...
10
votes
7answers
2k views
Would it help if you jump inside a free falling elevator?
Imagine you're trapped inside a free falling elevator. Would you decrease your impact impulse by jumping during the fall? When?
17
votes
6answers
6k views
Newton's cradle
Why, when one releases 2 balls in Newton's cradle, two balls on the opposite side bounce out at approximately the same speed as the 1st pair, rather than one ball at higher speed, or 3 balls at lower ...
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 ...
0
votes
1answer
204 views
What is the linear momentum of an inelastic and elastic collision?
The arrows in the figure represent the linear momentum of two balls before they collide. If the collision is perfectly inelastic, find the linear momentum after the collision. If the collision is ...
0
votes
0answers
44 views
What is the momentum of the system in the center of mass frame? [closed]
During a baseball game, a batter approaches the plate. The pitcher hurtles the ball in the direction of the batter at a speed of 85 miles per hour. The batter swings and makes contact with the ball. ...
4
votes
2answers
201 views
Could we use particle colliders as fusion generators?
So I know the basic gist is that fusion power's main issue is sustaining the fusion. I also know that there are two methods. The Torus method and the laser method. The torus magnetically contains ...
1
vote
2answers
989 views
Inelastic collision and conservation of linear and angular momentum
Is it possible for two spheres (a & b) to have an inelastic collision with BOTH the total linear and angular momentum preserved? I'm doing some physics simulation of some spheres attracting each ...
1
vote
1answer
80 views
Simulation of broken object
I was thinking and the following question came out:
how an object that is falling is simulated once it hits the ground?
Specifically, I would like to understand how one would be able to simulate the ...
1
vote
1answer
171 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 ...
3
votes
3answers
400 views
Newton's 3rd Law: How can I break things?
If I punch a wooden board hard enough and it breaks in two, has the board still exerted a force of equal magnitude on my fist?
When the board breaks in two due to my force, the halves have a ...
0
votes
3answers
239 views
Interaction between a Pair of Particles
We consider a particle, A receiving energy from a second one,particle B in a one dimensional collision.
$$E^2=p^2+m_0^2$$
$$EdE=pdp$$
For particle A:
$$E_AdE_A=p_Adp_A{\;\;\;\;\;\;}(1)$$
For ...
0
votes
1answer
108 views
Bullet fired at a series of partitions
Imagine a bullet fired at a series of partitions stacked one after the other. Given that the bullet looses half its velocity in crossing each partition, velocity of the same is a geometric ...
1
vote
1answer
440 views
Scattering problem: Converting the two-body lab frame problem into a one-body center-of-mass frame problem
I'm reading the section on scattering in Goldstein's Classical Mechanics, and I have a rather basic question about this.
It says that scattering in the laboratory is a two-body problem because of ...
0
votes
1answer
180 views
Scattering problem: Finding the speed of the scatterer after collision
A particle of mass $M$ moving in a straight line with speed $v$ collides with a stationary particle of the same mass. In the center of mass coordinate system, the first particle is deflected by 90 ...
0
votes
0answers
62 views
Hypersonic collisions: how to understand
Preliminary: I'm not good with tensor calculus, but it's okay for me to work with reasonably complex differential equations.
What I need is understanding of process of high speed (5-500 km/s) ...
5
votes
4answers
2k views
The Time That 2 Masses Will Collide Due To Newtonian Gravity
My friend and I have been wracking our heads with this one for the past 3 hours...
We have 2 point masses, $m$ and $M$ in a perfect world separated by radius r. Starting from rest, they both begin to ...
1
vote
2answers
128 views
Unexpected potential energy increase during Tic-Tac drop
I dropped a Tic-Tac:
(no worries, it happened before), and I noticed as it bounced on the floor that it would first jump 20 cm high, and at the next bounce for instance 50 cm high. Shouldn't it ...
2
votes
1answer
65 views
Is Joule heating only between charged particles?
The Wikipedia page for Joule heating explains
"It is now known that Joule heating is caused by interactions between the moving particles that form the current (usually, but not always, electrons) and ...
2
votes
3answers
182 views
The theory of moon creation when a Mars size planet hit Earth
As we know the predominant theory where does the moon come from is that a Mars size planet hit the earth and took a chunk out of it which eventually materialized into moon.
My question is that if a ...
5
votes
1answer
257 views
What's worse, a full frontal impact or an impact at an offset?
Modern car designs have a crumple zone that absorbs most of the impact in a collision, and a strong "safety cell" in the passenger compartment that protects the passengers. These designs are put to ...
0
votes
1answer
76 views
Future of colliders and technical limitations
Are there any technical limitations (theoretical or technological) that prevent quark based colliders? ie. Colliding two quarks together.
3
votes
1answer
548 views
What phrases describe collisions with coefficients of restitution less than zero or greater than one?
The coefficient of restitution describes the elasticity of a collision:
1 = perfectly elastic, kinetic energy is conserved
0 = perfectly inelastic, the objects move at the same speed post impact
...
3
votes
1answer
209 views
Anti-Matter for Neutrons
The anti-particle corresponding to a proton or an electron is a particle with an equal mass, but an opposite charge. So what is the anti-particle corresponding to a neutron (which does not possess a ...
3
votes
1answer
170 views
What is the function of the top point of a bouncing ball?
A ball is thrown away as parallel to x axis from M(0,h) point with speed V . After each jumping on x axis , it can reach half of previous height as shown in the figure.(Assume that no any air ...
1
vote
1answer
103 views
Could ions emitted by an ion thruster represent any realistic danger?
As ion thurster designs improve, the ions emitted could have a velocity (relative to the spacecraft) of well above 10^5 or even 10^6 m/s.
It the likelihood of any such ions ever hitting a human ...
-3
votes
1answer
141 views
Mathematical question on Collisions [closed]
A 2.5kg ball travelling with a speed of 7.5m/s makes an elastic
collision with another ball of ...
1
vote
2answers
221 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 ...
1
vote
1answer
538 views
Finding force exerted in an Inelastic Collision
I did a lab today in Physics in which we launched ball from a spring loaded cannon directly into a pendulum that captured the ball, held it, and swung upwards with it (representing a totally inelastic ...
1
vote
2answers
1k views
What are all the equations we use to calculate how bounces work?
I mean, what is the object's final displacement, or the function that describes the object's height over time (see [1]) of an object thrown by a height $h$ with a speed of $\vec{v_0}$, a mass of $m$, ...
0
votes
1answer
176 views
Friction + Bouncing of an Object against an Elastic Wall
I am trying to create the formula for applying a bouncing effect to an element which is already slowing down by friction.
At the moment I have an element which moves in one dimension at speed "S" and ...
0
votes
2answers
647 views
Two objects exert forces on each other, will the reactions affect them?
Two objects go in against each other, and then they collide, will object 1, exerting force 1, necessarily get on it a reaction equal in magnitude and opposite in direction?
EDIT:-
In my book it only ...
-1
votes
1answer
258 views
Minimal kinetic energy during elastic collision [closed]
Two wagons, moving towards each other along a straight line, collide. The first wagon has the speed 3 m/s and the weight 3 kg. The second wagon has the speed 1 m/s and the weight 1 kg. The collision ...
2
votes
3answers
258 views
Train crash: are these situations alike?
I was just wondering... I believe that if a car travelling 50 miles per hour crashes into a wall, the result should be the same as crashing to another car also travelling 50 miles per hour (but in the ...
1
vote
2answers
548 views
Calculating Impact Velocity Given Displacement and Acceleration
Assume a car has hit a wall in a right angled collision and the front bumper has been displaced 9 cm. The resulting impact is 25g. Also, it is evident by skid marks that the car braked for 5m with ...
2
votes
0answers
263 views
kinetic energy in collisions
We were hoping you could help us understand collision energy.
Vehicle A is driving West at 35mph and weighs 1437kg.
Vehicle B is driving North at 35 mph and weighs 1882kg.
Vehicle B crashes into the ...
3
votes
2answers
834 views
What causes destruction in car crash?
Suppose a car crashes at a speed $v$ against a wall and comes to a stop. Now if the car crashes at $2v$, does that mean it suffers twice as much destruction, if that can be objectively measured?
If ...
0
votes
1answer
416 views
How to calculate the coefficient of restitution for 2 bodies?
I have 2 rigid bodies (from different materials) in a collision.
As you know I should have the coefficient of restitution value to get the velocities after collision.
What is the information/values ...
0
votes
1answer
29 views
How much energy should I give into each particle in this equation:
I am trying to recreate the results of an article (membrane simulation) and I have the following line:
Both particles have the same soft radius,
$U_{rep} (r)/\epsilon = \text{exp}\left\{ -20 ...
3
votes
2answers
934 views
Conservation of Momentum/Energy collision Problem
I'm working on a physics problem in preparation for the MCAT and there's this particular problem that's troubling me. I don't know if it's a bad question or if I'm not understanding some sort of ...
1
vote
0answers
102 views
Calculating collisions in realtime - dealing with a delay in time [closed]
I wasn't sure in which stackexchange to post this, since the questions deals with a lot of different topics. I've posted it first at stackoverflow, but I've been redirected here...
Suppose:
You're ...
1
vote
1answer
2k 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 ...
5
votes
3answers
270 views
the collision of Phobos
Mars has two moons: Phobos and Deimos. Both are irregular and are believed to have been captured from the nearby asteroid belt.
Phobos always shows the same face to Mars because of tidal forces ...
1
vote
1answer
68 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 ...
4
votes
3answers
296 views
Only Head On collision?
Let us consider two spheres A and B. Suppose they are interacting with each other (In broad sense one can say they are colliding). Let for the time being refer to "striking by coming in contact as ...
1
vote
0answers
161 views
How to calculate the resulting velocitys and rotation speed after two concave polygons collide in 2d
so I've been searching google for how to do this, but all anyone seems to care about is collision detection =p, and no results come close to teaching me how to calculate 2d elastic collision between ...
4
votes
1answer
236 views
How and why will the Milky way collide with the Andromeda?
Hubble's law says that the universe is expanding.How come the milky way and the andromeda are on a collision course?How will they end up colliding with each other?
0
votes
0answers
72 views
Bouncing back of a ball [duplicate]
Possible Duplicate:
Physics of simple collisions
Let the unit vector along the positive x- axis be i and that along the Y-axis be j. Let us consider a rigid wall with the normal to the ...
