What is Collisions: Definition and 706 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.
H guys,
I want to first start off by saying that I am not here for handout to my homework. I am here because maybe you guys can help me understand physics. I am currently enrolled in a calculus-base physics that is kicking my ass and I need some help understand the different subjects...
Homework Statement
We have two particles mass m called p1 and p2. P1 is stationary, p2 has energy E. They annihilate to produce to particles of mass 100m. We need to find the min value of E
Homework Equations
The Attempt at a Solution
I suspect that the minimum initial energy of...
Homework Statement
There is a frictionless table 1 meter above the ground. A spring is on one end of the table with a constant of 200N*m that is compressed .5m by a block of 5kg. The block of 5kg is released and then collides with a 2kg block also sitting on the table.
a. Find the velocity...
You are at the controls of a particle accelerator, sending beam of 2.70*10^7 m/s protons (mass m) at a gas target of an unknown element. Your detector tells you that some protons bounce straight back after a collision with one of the nuclei of the unknown element. All such protons rebound with a...
This is an angular inelastic collision problem:
Mary, Bob and Jane are having a snowball fight. Mary throws a 50g snowball 60 degrees S of E at 6 m/s. Bob throws his 15g snowball 2.75m/s north. Jane's throws her 35g snowball at 3.25m/s west. How fast and what is the direction of the huge...
This might be stupid but I was thinking, when two subatomic particles collide at very high speeds, they form a bigger particle whose mass is less than the sum of the smaller ones, and the mass lost transforms into energy as in Einstein´s equation E=mc2.
What happens with non subatomic...
A 49 g steel ball is released from rest and falls vertically onto a steel plate. The ball strikes the plate and is in contact with it for 0.5 ms. The ball rebounds elastically and returns to its original height. The time interval for a round trip is 7.00 s. In this situation, the average force...
Hi, I am having problems with a particular question it says:
Two 30kg children, each with a speed of 4.0m/s, are sliding on a frictionless frozen pond when they collide and stick together because they have Velcro straps on their jackets. The two children then collide and stick to a 75kg man...
When two masses collide, assuming there are no external forces on the system of the two masses, will they collide with the same velocities or will it depend on the conserved momentum?
Edit -- Assume they're released from rest, since that's what the problem I'm working on states.
My question is not so much what to do it is just i have problems solving for a certain equation.
A 5.00kg ball, moving to the right at a velocity of 2m/s on a frictionless table, collides head-on with a stationary 7.50kg ball. Find the final velocities of the balls if the collision is (a)...
I was reading about what would happen if an Anti-Matter star and Matter star collided. What I read says the collision would make enough gamma rays to sterilize and entire eighth of a galaxy of life.
Yet, I thought about something, when the two collide, their surfaces would touch first. (Duh) So...
Please do not answer these, just give hints
A block of mass M is connected to a second block of mass m by a linear spinrg of natural length 8a. When the system is in equilibrium with the first block on the floor, and with the spring and second block vertically above it, the length of the spring...
In a nuclear reactor, neutrons released by nuclear fission must be slowed down before they can trigger additional reactions in other nuclei. To see what sort of material is most effective in slowing (or moderating) a neutron, calculate the ratio of a neutron's final kinetic energy to its initial...
Imagine that two vehicles traveling on a frictionless surface crash into each other. Vehicle A is traveling due north, vehicle B is traveling due east, they smash into each other, and B skirts off at an angle exactly 60 degrees south of east while A skirts off at an angle exactly 60 degrees...
The Problem:
The drawing shows a collision between two pucks on an air-hockey table. Puck A has a mass of 0.025 kg and is moving along the x-axis with a velocity of +5.5 m/s. It makes a collision with puck B, which has a mass of 0.050 kg and is initially at rest. The collision is not head-on...
can anyone offer up some help? I've been working on this forever with no success.
On a frictionless surface, a 0.35 kg puck moves horizontally to the right (at an angle of 0°) and a speed of 2.3 m/s. It collides with a 0.23 kg puck that is stationary. After the collision, the puck that was...
Here's the problem:
"Two steel balls are suspended on (massless) wires so that their centers align. One ball, with mass 2.30 kg, is pulled up and to the side so that it is 0.0110 m above its original position. Then it is released and strikes the other ball in an elastic collision. If the...
# In a perfectly elastic relativistic collision, which one of the following quantities is not conserved:
a)Momentum
b)Energy
c)Rest mass
d)Angular momentum
In non relativistic elastic collisions, energy and momentum will be conserved. But I don’t know about relativistic elastic collisions...
I was assigned this problem from my physics teacher, but it doesn't really make sense. I would ask the teacher, but I don't go back to class for a few days. At this point, I just need help trying to understand what the problem is asking for. Thanks very much in advance for any help.
Find the...
A 56g steel ball is released from rest and falls vertically onto a steel plate. The ball strikes the plate and is in contact with it for .5ms. The ball rebounds elastically, and returns to its original height. The time interval for a round trip is 8.00s. In this situation, the average force...
In a volume V there exist N particles of diameter d.
If we place some detector in this volume, what is the probability that the detector will measure a collision in a time interval t. Or what is the probability that the detector will travel some specified distance into this volume.
There...
My question is "If I have an immobilised substrate (protein molecule), is it more likely that when in a solution with enzymes(which are free to move) that a collision will occur than if the substrate was mobile.
Any input would be appreciated :smile:
Ok. I need help in how to even just start this problem.
"Starting with an initial speed of 5.00 m/s at a height of 0.280 m, the 1.75 kg ball swings downward and strikes the 4.75 kg ball that is at rest.
a) Using the principle of conservation of mechanical energy, find the speed of the 1.75...
After a completely inelastic collision, two objects of the same mass and same initial speed are found to move away together at 1/4 their initial speed. Find the angle between the initial velocities of the objects.
I figured.. 2m(v/4)
but then i just get lost... can someone help! thanks!
Hi guys!
I was hoping that some of you smart guys and gals might be able to help me.
I'm looking for the simplest way to describe a series of collisions. Basically, an object colliding with another object, then a time delay and then another object colliding with the first two and so on...
Q.
A 0.150 kg billiard ball (A) is rolling toward a stationary billiard ball (B) at 10.0 m/s. After the collision, ball A rolls off at 7.7 m/s at an andle of 40.0 degrees clockwise from its original direction. What is the speed and direction of Ball B after the collision?
Known:
M of...
Can anyone tell me what i am doing wrong for this problem?
Two 75 kg hockey players skating at 5.75 m.s collide and stick together. If the angle btween their initial directions was 125 degrees, what is their velocity after the collision?
I used the formula Vf = m1v1/(m1+m2) cos 125 for the x...
i need a help on this problem
a 20g rifle bullet traveling 250m/s buries itself in a 3.8kg pendulum hanging on a 2.3m-long string. how far does th ependulum swing horizontally?
Physics 3rd edition Douglas C. Giancoli
i need help for this problem
if anyone could solve this, it's wonderful
A 20g rifle bullet traveling 250m/s buries it self in a 3.8kg pendulum hanging on a 2.3m-long string. how far does the pendulum swing horizontally?
Physics 3rd edition Douglas C. Giancoli
a 11.9g bullet is fired vertically into a 5.49kg block of wood. the bullet gets stuck in the block, and the impact lifts the block 0.11m up. given g=9.8m/s^2. what was the initial velocity of the bullet?
Pi=Pf is this right...
Hi,
I would like somebody to verify if I have correctly solved a problem.
The problem is this: Rock of mass m falls from height 20 m to the ground. What is the average force of the ground acting on the rock if it takes 0.025 s to bring the rock to full stop. Express the force in relation to...
Hi there,
i've been coding a simulator (ellastic collisions with billard balls) and i wanted to check if the results the program outputs are indeed valid.
My doubts are with multiple collisions at the exact same instant and with kinetic energy as well.
.
Just to make clear, a possible...
having trouble with this problem in my textbook
two pucks collide, puck A has a mass of 0.32kg, and an initial velocity of 0.04 m/s [54 N of E], and a final velocity of 0.034 m/s [N]
puck B's mass is unknown but has an initial velocity of 0.038 m/s [S of W] and a final velocity of 0.028 m/s...
I have been dueling with this problem for a hour or so now...
a 5.00g bullet moving with an initial speed of 400 m/s is fired into and passes through a 1.00-kg block. The block, initially at rest on a frictionless, horizontal surface, is connected to a spring with a force constant of 900 n/m...
dear god i just typed a full page and it decided to give me a 404, i hate computers.
First time i had to use this forum in a long time but I am very stuck today and can't find a way out of it after over an hour and with reading my notes so here goes.
1)a proton of mass m traveling at...
well first time i have had to use this forum in a long time, but i am very stuck (i guess being hungover and falling asleep in the lecture didnt help)
but i have 2 problems that i have been playing with for over an hour now and just cannot get any kind of reasonable answer
1) a proton of...
Lets say that there is a man flying in a spaceship going fast enough that to another observer standing on the Earth he appears to be twice as big as normal due to relativistic mass (I might be wrong here, and relativistic mass doesn't make you look bigger). From the man's frame he would say he...
Please Help! 2 Question involving momentum and collisions
Just some questions in calc-based physics. Thanks in advance.
1) A 25 kg child is in a 10 kg sled that travels 1 m/s east on ice. The child throws a 3 kg snowball at 40 m/s at an angle of 50 degrees north of east. Find the velocity of...
How would I go about this problem? Any advice would be really helpful, please.
A bat strikes a 0.154 kg baseball. Just before the impact, the ball is traveling horizontally to the right at 50m/s, and it leaves the bat traveling to the left at an angle of 30 degrees about the horizontal with a...
Impulse
1) A gold ball of mass 0.045 kg is hit off the tee at a speed of 45 m/s. The golf club was in contact with the ball for 3.5 x 10^-3 s. Find (a) the impulse imparted to the golf ball and (b) The average force exerted on the ball by the golf club.
Answer: (a) 2.0 kg(m/s) (b) 15.8 x 10^2...
In the kinetic theory, it is supposed that the molecules make elastic collisions with the walls of the container. Imagine that the collisions were inelastic. Describe and explain the consequence of this with regard to the temperature of the gas.
So far, i have said that not all of the molecules...
Two particles of masses M and 3M are moving towards each other along the +x and -x directions with the same initial speed 3.29 m/s. They undergo a 'head-on' elastic collision and each rebounds along the same line as it approached. What is the final speed of the particle of mass M in m/s?
so i...
Two blocks can collide in a one-dimensional collision. The block on the left hass a mass of 0.50 kg and is initially moving to the right at 2.4 m/s toward a second block of mass 0.80 kg that is initially at rest. When the blocks collide, a cocked spring releases 1.2 J of energy into the system...
Hey hey!:biggrin:
A 10g object moving to the right with a speed of 20cm/s makes an elastic head-on collision with a 15g object moving in the opposite direction with a speed of 30cm/s. Find the velocity of each object after the collision.
So I have to come up with two equations and solve for...
I have a problem in which two objects collide (elastic) in two dimensions. I am given the vectorial components of the initial velocities of each object as well as their masses, which are different. I also know the final velocity of the smaller object, which is 0 (it comes to rest after the...
I am try to write a program with 3D spheres of different masses, radius, velocities and angles. Then use three dimensional elastic collision equations to find the spheres new velocities and angles. The problem is that i can't find any information or equations on 3D elastic collisions, only 1D...
Hi all,
I was wondering if someone can help me, its been a while since I did classical mechanics, I have a question I would appreciate a little help from anyone!
2 objects with the same mass m and same velocity v have an inelastic collision . After the collision the 2 object system of...
Here's my problem:
Car A (mass 970 kg) is stopped at a traffic light when it is rear-ended by car B (mass 1600 kg). Both cars then slide with locked wheels until the frictional force from the slick road (with a low mk of 0.23) stops them, at distances dA = 5.8 m and dB = 3.6 m. What are the...