What is Collision: Definition and 1000 Discussions
In physics, a collision is any event in which two or more bodies exert forces on each other in a relatively short time. Although the most common use of the word collision refers to incidents in which two or more objects collide with great force, the scientific use of the term implies nothing about the magnitude of the force.
Some examples of physical interactions that scientists would consider collisions are the following:
When an insect lands on a plant's leaf, its legs are said to collide with the leaf.
When a cat strides across a lawn, each contact that its paws make with the ground is considered a collision, as well as each brush of its fur against a blade of grass.
When a boxer throws a punch, their fist is said to collide with the opponent's body.
When an astronomical object merges with a black hole, they are considered to collide.Some colloquial uses of the word collision are the following:
A traffic collision involves at least one automobile.
A mid-air collision occurs between airplanes.
A ship collision accurately involves at least two moving maritime vessels hitting each other; the related term, allision, describes when a moving ship strikes a stationary object (often, but not always, another ship).
In physics, collisions can be classified by the change in the total kinetic energy of the system before and after the collision:
If most or all of the total kinetic energy is lost (dissipated as heat, sound, etc. or absorbed by the objects themselves), the collision is said to be inelastic; such collisions involve objects coming to a full stop. An example of such a collision is a car crash, as cars crumple inward when crashing, rather than bouncing off of each other. This is by design, for the safety of the occupants and bystanders should a crash occur - the frame of the car absorbs the energy of the crash instead.
If most of the kinetic energy is conserved (i.e. the objects continue moving afterwards), the collision is said to be elastic. An example of this is a baseball bat hitting a baseball - the kinetic energy of the bat is transferred to the ball, greatly increasing the ball's velocity. The sound of the bat hitting the ball represents the loss of energy.
And if all of the total kinetic energy is conserved (i.e. no energy is released as sound, heat, etc.), the collision is said to be perfectly elastic. Such a system is an idealization and cannot occur in reality, due to the second law of thermodynamics.
Homework Statement
A ball A is dropped from the top of a building of height h and simultaneously a ball B is thrown upwards and both balls collide. After the collision the ball A has the double the velocity of ball B
Determine the fraction of the building where the balls collide...
A ball (mass m1 = 2 kg, velocity v = 5 m/s [the ball moves horizontally]) collides with another ball (mass m2 = 8 kg) which is hanging on a string (length l = 1.35 m). The collision is completely elastic. What is the tension force affecting the ball (m2) immediately after the collision?
I...
Homework Statement
A car with a mass of 1200 kg and a speed of 70 km/h collides in a head-on collision with a motorcycle. The vehicles lock together and continue along with the speed of 45 km / h in the cars original direction. The motorcycle weighing 250 kg.
What is the speed of the...
Which bulb is really more collisions of electrons inparallel connection?
Maybe we can easily get the conclusion about this question.
The intensity of bulb's light is depend on the power of electricity(IV), so the upper blub has more number of collisons between electrons and atoms.
but I...
This isn't actually a homework problem, I'm just wondering what I'm doing wrong:
Homework Statement
Say we've got a stationary brick wall, and a blob of jello with mass m is launched at the wall with speed v. The blob has length d along the direction of motion.
The blob splatters...
Could anyone guide me through this problem?
https://www.physicsforums.com/showthread.php?t=348863
Just need to get started. Note that this would need to be solved in the proton rest frame.
Homework Statement
A particle of mass ##m_1## collides elastically with a stationary particle of mass ##m_2## (##m_1>m_2##). Find the maximum angle through which the striking particle may be deviated as a result of the collision.
(Ans. ##\sin(\theta_{max})=m_2/m_1##)
Homework Equations
The...
Homework Statement
In a crash test a solid concrete wall is
used to test crashworthiness. A particular
SUV weighs 338.183 kg and is accelerated to
33.3485 m/s before colliding head on with the
barrier.
What impulse must be applied is required
to stop the SUV?
This gives Impulse =...
Hello everyone, My Name is Dwayne McIntosh.
I am not that good at Physics or Mathematics however i do have a problem.
I was brainstorming the other day and i wanted to know, what if one was to use say electromagnetic waves (may be different wavelength,frequency or Photon Energy, but with...
This isn't an actual homework problem, but it feels like it could be.
Homework Statement
Two masses, m1 and m2 are involved in an elastic collision. The initial velocities v1_0 and v2_0 are 1 and -2, respectively. The final velocities v1_1 and v2_1 are -3 and 0, respectively. Solve for...
(Q) A Ford car of mass 1138kg, collides with a Vauxhall car, of mass 1849kg, stationary at a stop line. The ford stops immediately but pushes the Vauxhall forward 13.42m. Was the Ford traveling over 13.41m/s before the collision?
I can't seem to find a solution as everything I have tried...
Homework Statement
"Consider a head-on, elastic collision between two modies whose masses are m and M, with m << M. It is well known that if m has speed v_0 and M is initially t rest, m will bounce straight back with its speed unchanged, while M will remain at rest (to an excellent...
Homework Statement
A particle of mass ##m_1## experienced a perfectly elastic collision with a stationary particle of mass ##m_2##. What fraction of the kinetic energy does the striking particle lose, if it recoils at right angles to its original motion direction.
(Ans: ##2m_1/(m_1+m_2)## )...
Homework Statement
Using the equation for the final velocity of an inelastic collision, show that mechanical energy is not conserved in the collision. (Do this only with variables.)Homework Equations
Vf = (m1v1i + m2v2i)/(m1 + m2)
KE = (1/2)mv2
TME = KE + PEThe Attempt at a Solution
I honestly...
Homework Statement
2 particles travel towards each other at 10ms-1. Particle 1 has a mass of 10kg and particle 2 has a mass of 30kg. It is an inelastic collision.
Find the magnitude of the Impulse of particle 1 and 2.
Homework Equations
I=Ft=mv-mu
m1u1+m2u2=(m1+m2)V
The Attempt at...
Homework Statement
A uniform bar of mass m and length l is suspended on a frictionless hinge. A horizontally launched blob of clay of mass m strikes the bottom end of the bar and sticks to it. After that, the bar swings upward. What is the minimum initial speed v of the blob of clay that...
Homework Statement
A rod of mass M is lying on a flat frictionless surface. A small ball of mass m and
velocity v collides with the rod in the center at the rod at right angle to the rod.
The collision is elastic.
Homework Equations
a) Where is the axis of rotation for the rod...
Is it is true that all elastic collision are like rubber balls, then how does indivisible particles collide if they can't change their shape, that is store the energy inside like rubber balls and then release it?
Lets say an archer shoots an arrow or a gun fires a bullet, why is it that a lighter objects (arrow and a bullet) gain larger kinetic energy than the heavier one's? Shouldn't it be Newtons 3rd law: force from the gun powder at the equal distance hence same gained kinetic energy?
Possible "criteria" or parameters for planetary collision?
Suppose a computer model were created to simulate two proto-type planets on a collision course (for example, the Earth-Moon collision in the Hartman theory of the Moon formation). We know that the Moon is spiraling outwards (tidal...
Show that the kinetic energy of the Earth after a collision can be ignored (stuck & desperately need help)?
A ball of mass m2 is dropped and bounces off the floor. If the impact is viewed as an elastic collision between the ball and the earth, show that the kinetic energy of the Earth after the...
Homework Statement
Ball A with mass 4 kg is moving with a velocity of 8 m/s North when it crashes into Ball B with unknown mass moving with a velocity of 6 m/s West. This collision is perfectly elastic. If Ball A ends up moving with a velocity of 6.5 m/s @ 120° after the collision, find the...
Collision Question: (URGENT) Exam tomorrow
Hi all,
I have an exam on collision and projectile motion tomorrow, and was wondering if anyone could answer this question: I get an answer, but my friend gets a completely different answer. I was wondering if anyone could just clarify and show us the...
Homework Statement
Two balls collide on a frictionless surface. Mass m1 = .4 kg and Mass m2 = .3 kg . The initial velocity of m1 is 3 m/s. While m2 is at rest. After the collision the velocity of m1 is 1.5 m/s, θ1 above the horizontal. While m2 gains an unknown velocity of v2f, θ2 below the...
Homework Statement
A smooth sphere of mass m collides obliquely with a smooth sphere of mass 2m which is at rest.The velocity of the mass m was 8i + 4j before impact, where i is along the lines of centres at impact.the m mass is then deflected through 90 degreese by the impact. find
(i) its...
Homework Statement
A smooth sphere of mass 4 kg collides obliquely with another smooth sphere of mass m which is at rest.After impact the two spheres move at right angles to each other.If the coefficient of restitution was (4/7), calculate the value of m.
Homework Equations
m1u1 + m2u2...
These are the instructions:
What to do:
1. Connect the two photogates to DIG 1 and DIG 2 ports of the LabQuest device. Connect this device to a computer and turn on the device.
2. Open Logger Pro 3.8.4 software. Click Folder icon/symbol. Open Probes & Sensors > Photogates > Two Gate Timing.
3...
Hello. I am new to these forums. I don't really know if this is the right place to post this, but here it goes.
I was thinking, what If there were two bodies (represented by points) in space (two dimensional space to keep it simple) with known position at time zero, where the first is moving...
Homework Statement
A ball of mass 100 g is projected straight up with a speed of 5 m/s from the floor. Another ball of mass 50 g is hung from the ceiling by a light string at a height of 1.00 m directly above the first ball, so that the projected ball collides elastically with it. Calculate...
Following on from my (still not quite solved) question here: Calculating event time using gsl_poly_solve_quadratic
I'm now looking to calculate the collision response (new linear velocity vector) for the sphere after a collision with a line (rail).
The current code I'm extending has two...
Suppose a bubble with some small mass and constant velocity hits a bundle of "bubbles"- the collision is unusual- there is no dynamic friction but the point of contact sticks- they are springy so both compress by a third before returning to their former shape. The new total bundle can't...
Homework Statement
An unlikely weapon was once proposed which had all of the people in China to jump up and down simultaneously. Let us say there are 2 billion people (2.0 x 10^9) with an average mass of 50 kg. They all climb ladders which are 1 meter tall. At a particular instant they all...
Help slove pls!:(
A uniform smooth sphere P,of mass 3m, is moving in a straight line with speed u on a smooth horizontal table.Another uniform smooth sphere Q, of mass and m and having the same radius as P, moving with speed 2u in the same straight line as P but in the opposite direction to P...
Homework Statement
A ball of mass m moves horizontally with speed 20 m/s towards a smooth barrier xy which makes an angle tan-inverse(4/3) with the horizontal.The coefficient of restitution is (3/4)
find
(i) The speed of the ball after the impact
(ii) The magnitude of the impulse due to...
Homework Statement
I am designing a physics simulation that models two balls colliding along a straight line path. I can change the coefficient of restitution, the initial velocities, and their masses. THe assignment asks that we vary at least three parameters, so in my case, the three are...
It appears that a big planet size body collided with Jupiter in the recent past, What all are the evidences required to prove a recent big collision on a planet?
1) Jupiter's diameter was increased nearly 50% when comparing modern values with ancient Indian astronomical text Surya-siddhanta...
A 0.440kg ice puck, moving east with a speed of 3.16m/s, has a head-on collision with a 0.940kg puck initially at rest. Assuming a perfectly elastic collision, what is the speed of the lighter puck? Use east as the positive axis.
I got -2.09.
I made two equations and used substitution to...
Homework Statement
A 67.6g tennis ball with an initial speed of 28.8m/s hits a wall and rebounds with the same speed. The figure below shows the force of the wall on the ball during the collision. What is the value of Fmax, the maximum value of the contact force during the collision, if the...
Ok.. So basically 100kg object V100 is coming from left to right at 20m/s and 50kg object V50 is coming from right to left at 35m/s and make collision. They get pushed away like on picture.
I need to find V50 and V100 but from the looks of it, I need to find angle theta to find an answer. How...
Hello all,
I am attempting to simulate collisions of pool balls. For the moment i am doing so without taking rotational momentum or friction between balls into account. right now i have a system that successfully simulates a collision between 1 ball and another ball. Here's how it basically...
Hello,
I've been trying to figure out the physica behind a collision of two objects due to the force of gravity. Here's the situation as I'm picturing it:
A massive object A is falling due to gravity which impacts a stationary object B being held up by a structure. In this particular case...
Homework Statement
A block with mass 4 kg and velocity of 3 m/s collides elastically with block B with mass 2 kg which is originally at rest. Find the velocities of the two blocks after the collision.Homework Equations
P= m * vThe Attempt at a Solution
This is the first time I try to solve an...
Hi guys,
I've been thinking on a problem for a while which really bothers me. I've been trying to mathematically solve the following problem:
A train approaches the station at a velocity of V=50 m/s. Then a tennis ball is thrown with a velocity U=30 m/s, against the approaching train...
Homework Statement
I was given the following problem and I an trying to discover if it can be answered by transforming to the center of mass frame and then transforming back.
"Consider a perfectly elastic collision between a particle moving with kinetic energy 10 times its rest mass energy...
Homework Statement
Homework Equations
The Attempt at a Solution
I've done part (a) and (b) using conservation of momentum and energy..for part (c) I'm not sure how to find the minimum angle ∅. I have also worked out the velocities of m1 and m2 just before the collision as...
Hi all,
I would like to ask why only Protons were selected for collision in LHC project? Why not other fundamental particles?
When I was watching the programme on big bang by Michio Kaku and Lawrence Krauss, they were saying at the earliest instant of big bang, there were four forces...
Homework Statement
Three spheres, each of mass m, can slide freely on a frictionless, horizontal surface. Spheres A and B are attached to an inextensible inelastic cord of length / and are at rest in the position shown when sphere B is struck directly by sphere C which is moving to the right...
Homework Statement
A 0.2 kg block, moving at 6 m/s, is catching up and colliding elastically with a 0.6 kg block that is moving along the same line and in the same direction. Find the velocities of the ball after this one-dimensional collision.
Homework Equations
Conservation of...
Homework Statement
A solid sphere rolling on a rough horizontal surface with a linear speed ##v## collides elastically with a fixed smooth, vertical wall. Find the speed of the sphere after it has started pure rolling in backward direction.
Homework Equations
The Attempt at a...