Elastic collision Definition and 531 Threads

Hi guys. There is a question that confusing me for a long time. If an elastic collision occur, do I need to consider the positive and negative sign?? According to my teacher, an object moves in the opposite direction we need to consider the sign. Is it works in this situation?

Homework Statement A 2D elastic collision: Two pucks (masses m1 = 0.5 kg and m2 = 0.3 kg) collide on a frictionless air-hockey table. Puck 1 has an initial velocity of 4 m/s in the positive x direction and a final velocity of 2 m/s in an unknown direction, θ. Puck 2 is initially at rest. Find...

Homework Statement Consider a collision: If mass 1 has initial velocity 1i-1j of and mass 2 is initially at rest. After collision mass one moves with a velocity of 2i-3j and mass 2 moves with velocity of -1.5i+3j. What's m1/m2? Homework Equations m1/m2-=(v2f-v2i)/(v1i-v2f) The Attempt at a...

Homework Statement A low-energy particle collides elastically with a stationary particle of the same mass. The angle between the subsequent paths of both particles are 90 degrees. But when a high-energy proton collides with a stationary proton, the angle between the two paths is not 90 degrees...

Homework Statement The problem is pretty simple, however I don't understand which value to use after using quad formula to solve. See below. V1(initial) = 2.5 m/s V2(Initial) = -5.9 m/s A pool ball moving with a speed of 2.5 m/s makes an elastic head-on collision with an identical ball...

This is the problem I am looking to solve: given two objects of different mass, find the angle of deflection after an elastic collision for each object. For both objects we know: m : Mass in Kilograms θi : Initial Angle in Degrees si : Initial Speed in Units per Second sf : Final Speed in...

Homework Statement A curling stone with initial speed vi1 collides head-on with a second, stationary stone of identical mass, m. Calculate the final speeds of the two curling stones. Homework Equations See attached picture The Attempt at a Solution I solved for vf1 as shown, but my answer...

Homework Statement Two balls collide in a perfectly elastic collision. Ball 1 has a mass of 3.5kg and is initially traveling at a velocity of 5.4m/s. It collides head-on with stationary ball 2 with mass 4.8kg. Determine the final velocity of ball 2. Given: m1=3.5kg vi1=5.4m/s m2=4.8kg...

Homework Statement If a object 1 & 2 collide as a perfectly inelastic collision, would they will both stop. Also If this same situation happened elastic? please explain if this is true or false and draw a free body diagram if possible. Homework Equations F=ma Newton second Law KE=1/2ma The...

Homework Statement 2 balls, their size is the same but mass is different, they are going towards a collision. I do not know what is the word for it in english but its like this m1= 1,2m2. Speed of the balls are v1=12m/s and v2= 15m/s.Calculate the speed of each ball after absolutely central...

Homework Statement In a fixed target experiment a particle of mass M and kinetic energy T strikes a stationary particle of mass M. By evaluating s, t and u in the laboratory frame and using the above relation, or otherwise, show that the kinetic energy T' of the particle scattered elastically...

Homework Statement The classic double ball drop question: a ball of mass m is placed directly above another ball of mass M, and assume that m is not negligible. Both balls are dropped simultaneously. Find the mass m such that, upon the second collision (m with M), M has a final velocity of...

I am a programmer trying to simulate some 2D balls bouncing about and colliding with each other. I have both the ball's velocity components before the collision and I am trying to solve for them. I went to wikipedia to find a formula to satisfy my needs and ran into this section...

Homework Statement Ball strikes inclined plane of infinite mass with velocity v vertically. Elastic collisions. Velocity and direction after collision? One way of solving is take components along and perpendicular to inclined plane and then solve easily. Is there any way to solve is using...

Homework Statement A ball of mass m rolls down a 3.0 m ramp inclined at 30° above the horizontal, rolls along a flat, friction less surface, and collides elastically with another ball of mass 2m, initially at rest. The second mass then moves along the surface and collides with a horizontally...

Homework Statement Problem: An object of mass m1 elastically collides with an object of mass m2 =(3/2) m1 that is initially at rest. The less massive object has speed v1 and travels at an angle of θ1with its original direction (x-axis) after collision; the more massive object has a speed of v2...

[Note: Thread moved by moderator] Hi! so I have a question I am unable to do and I've been trying it for 3 hours. The question had 2 parts, i figured out part a but cannot figure out part b. A) A 0.006kg ball is dropped from a height of 4.0m above the floor. Neglecting air resistance...

Homework Statement Two objects collide and bounce off one another. After the collision, object m1 = 2.74 kg moves off at 12.8 m/s at a heading of 295 degrees. Object m2 = 2.28 kg moves off at 12.8 m/s at a heading of 241 degrees. Initially, m2 was traveling at 11.1 m/s at a heading of 334...

Hi everyone. I've a question that i wondered since the high school. Let's take two identical particles (same mass) that collide frontally. Assume it's an elastic collision. We have to conservate both the momentum and kinetic energy: v_1 + v_2 = v'_1 + v'_1 v^2_1 + v^2_2 = v'^2_1 + v'^2_1...

Homework Statement Consider a frictionless track as shown (I will attach an image in a follow up post). A block of mass M1= 5.00 kg is released from point A. It makes a head-on elastic collision at B with a block of mass m2 = 10 kg that is initially at rest. Calculate the maximum height to...

Homework Statement Three blocks of identical mass are placed on a frictionless table as shown. The center block is at rest, whereas the other two blocks are moving directly towards it at identical speeds v. The center block is initially closer to the left block than the right one. All motion...

Homework Statement A 2.0 kg ball moving with a speed of 3.0 m/s hits, elastically, an identical stationary ball. If the first ball moves away with angle 30° to the original path, determine: a. the speed of the first ball after the collision. b. the speed and direction of the second ball after...

Hi all, I've been self-studying a first year uni introductory mechanics course, and I'm confused with the derivations involved in calculating the final state of an elastic collision in one dimension, given the initial state. So basically we have masses of m_1, m_2 with initial velocities v_1i...

Homework Statement hello! so i am trying to figure out how to calculate the resultant velocities and directions(angles/vectors) that two perfectly elastic spheres might travel in if they were to be hit simultaneously by a third sphere at an angle. all the spheres are of equal mass, initial...

Homework Statement So this is just something i came up with to check if i am understanding everything allright, it all comes down to collisions in regard to the center of mass So two "masses" experience a glancing collision M1: vi - 3m/s (refered to as v1i) ; m - 2Kg (m1) M2...

Homework Statement Two 1.0-kg carts are coupled together and placed on a very long horizontal track that is at rest in the Earth frame of reference. The combination is launched so that at t = 0 it is moving to the right at speed 2.0 m/s in the Earth frame, with cart #1 in front and cart #2 in...

Homework Statement A red and a blue rubber puck are free to slide along a frictionless air table. Each has a mass of 40 grams. They collide in an elastic collision. Initially the red one is at rest and the blue one is traveling in the x direction with a speed of 4 m/s. After the collision the...

Homework Statement When an alpha particle collides elastically with a nucleus, the nucleus recoils. Suppose a 3.94 MeV alpha particle has a head-on elastic collision with a gold nucleus that is initially at rest. What is the kinetic energy of (a) the recoiling nucleus and (b) the rebounding...

Homework Statement [/B] Person A fires a 222 g arrow towards an archery target at a speed of 109 m/s. Person B shoots a 190. g arrow moving in the same direction. This arrow moves with a speed of 290. m/s, catches up, and then collides with Person A's arrow. If the arrows collide in a...

Homework Statement Hi there! In this exercise, we are supposed to derive this formula for a 2-D elastic with two different masses: (x-U*v1)^2 + y^2 = (Uv1)^2 (example, two billiard balls), the second mass is at rest. It's a equation which leads to a circle where all of the possible p2' lie...

Homework Statement A red ball and blue ball are sliding on a frictionless surface, each ball has a mass of 40g. They collide in an elastic collision. Initially the red one is at rest and the blue one is traveling in the x direction with a speed of 4 m/s. After the collision the blue one is...

Homework Statement See picture Homework Equations p = p1 +p2 p = mv The Attempt at a Solution See picture, using equations for the velocity and using 90-tan-1(2) for the angle

Imagine you have an object of, say, 5kg moving in the positive x direction at 2m/s. So it has 10kgm/s of momentum. Now imagine an elastic collision from the y direction that gives the object another 10m/s in the positive y direction. Therefore its momentum doubles. Now we know that the...

Homework Statement a uranium atom traveling at speed 4 * m/s collides elastically with astationary hydrogen molcule. head on. what is the approximate finalspeed of the hydrogen molecule?Homework Equations The answer is about 8*10^4 m/s But, i tried many times and failed. The Attempt at a...

Wouldn't the explanation that fits fundamental laws (e.g. Conservation of E) while making the least asumptions be an ongoing bang-crunch-bang...scenario? Why couldn't expansion be eventually reigned in by forces, dark matter and the like - ultimately leading to contraction? Why shouldn't...

Homework Statement Two objects with equal masses undergo an elastic collision in 2 dimensions. Object 1 has an initial velocity u1 and object 2 is initially at rest. After the collision, object 1 is observed to have a velocity equal to 3/5 of it's initial velocity. What is the velocity of...

Homework Statement [/B] A 2.0 kg ball moving with a speed of 3.0 m/s hits, elastically, an identical stationary ball as shown. If the first ball moves away with angle 30° to the original path, determine: a. the speed of the first ball after the collision. b. the speed and direction of the...

Homework Statement [/B] A white billiard ball with mass mw = 1.53 kg is moving directly to the right with a speed of v = 3.25 m/s and collides elastically with a black billiard ball with the same mass mb = 1.53 kg that is initially at rest. The two collide elastically and the white ball ends...

Homework Statement A 2.0 kg ball moving with a speed of 3.0 m/s hits, elastically, an identical stationary ball. If the first ball moves away with angle 30° to the original path, determine: a. the speed of the first ball after the collision. b. the speed and direction of the second ball after...

Homework Statement a. Suppose two particles with mass $m$ and coordinates $x_1$, $x_2$ collides elastically, find the lagrangian and prove that the linear momentum is preserved. b. Find new coordiantes (and lagrangian) s.t. the linear momentum is conjugate to the cyclical coordinate. Homework...

Homework Statement An object of mass m1 traveling with velocity v1i has a perfectly elastic collision in which it rear ends and object of mass m2 (m2>>m1) traveling with velocity v2i. How must the velocity v1i relate to v2i if the mass m1 is to stop in its tracks (v1f=0)? What happens if...

Homework Statement Two blocks collide on a perfectly elastic collision, after sliding on a frictionless surface. va = 1m/s vb = 1m/s ma = 0.05kg mb = 0.03kb I need to find the speed of both blocks after the crash. Homework Equations Conservation of momentum: mava+mbvb = mava' + mbvb'...

Homework Statement 2. Homework Equations Elastic collision: KE conserved The Attempt at a Solution I don't think there's really anything to work out...why would the 2M block move right as well?

Homework Statement Show that the Form factor is ##\frac{3(sin x - x cos x)}{x^3}##. Homework EquationsThe Attempt at a Solution [/B] I know that the form factor is simply the Fourier transform of the normalized charge density: F(q) = \int \frac{\rho}{Z} e^{-i (\Delta \vec k) \cdot \vec r}...

Homework Statement A proton of mass m is moving with initial speed v0 directly toward the center of a nucleus of mass 31m, which is initially at rest. Because both carry positive electrical charge, they repel each other. Find the speed v' of the nucleus for the following conditions: a) the...

Homework Statement A 500 g billiard ball is going at 10 m/s [E] when it impacts 2 other identical billiard balls. Afterwards, you observe 2 of the balls moving at 2 m/s [30 W of S] and 3 m/s[45 N of E] respectively. Calculate the Energy lost in the collision. Homework Equations KE = 1/2mv^2...

Homework Statement A 0.159kg glider is moving to the right on a frictionless, horizontal air track with a speed of 0.870m/s . It has a head-on collision with a 0.310kg glider that is moving to the left with a speed of 2.15m/s . Suppose the collision is elastic. a) Find the magnitude of the...

[Moderator's note: No template because the thread had attracted a fair number of responses before being moved out of Classical] Hey it's my first post, so I apologize in advance if this is under the wrong forum category... I am just wondering if I did I do this right? If not can you please...

Homework Statement This is a solved problem-- http://web.mit.edu/8.01t/www/materials/InClass/IC_Sol_W13D1-10.pdf Homework EquationsThe Attempt at a Solution In the solution, they conserve energy and angular momentum. Can I conserve linear momentum? Also, can I use coefficient of restitution...

Hi, Suppose I perform a basic experiment of an elastic collision between 2 carts. I do not want the carts to touch each other so I adjust a permanent magnet to each cart and give each one a starting velocity. Carts get close to each other, kinetic energy is transformed into "potential magnetic...