What Are the Final Velocities of Ball A and Ball B After Collision?

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Homework Help Overview

The problem involves a collision between two balls, where ball A has a mass of 0.030 kg and an initial velocity of +5.5 m/s, while ball B has a mass of 0.055 kg and is initially at rest. The collision is not head-on, and the final velocities of both balls are to be determined based on the angles at which they separate after the collision.

Discussion Character

  • Exploratory, Assumption checking, Problem interpretation

Approaches and Questions Raised

  • Participants discuss the conservation of momentum and energy equations relevant to the collision. There is uncertainty about how to solve for two unknown final velocities without additional information. Questions arise regarding the use of angles provided in the problem to assist in finding these velocities.

Discussion Status

Participants are actively exploring the problem, with some suggesting the need for multiple equations to solve for the unknowns. There is a recognition that two equations are necessary for the two unknowns, and some guidance has been offered regarding the approach to take, though no consensus has been reached on the best method to proceed.

Contextual Notes

Participants note the challenge of solving for two variables without knowing at least one of the final velocities. The angles of separation after the collision are mentioned as potentially useful information, but their application remains unclear.

Meco
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Homework Statement


The drawing shows a collision between two balls. Ball A has a mass of .030kg and is moving along the x-axis with a velocity of +5.5 m/s. It makes a collision with ball B, which has a mass of .055kg and is initially at rest. The collision is not head-on. After the collision, the two balls fly apart with the angles shown in the drawing below
What is the final velocity of ball A and B?

... ... | Ball A
... ... | 65°
. A ---B---
... ... | 37°
... ... | Ball B

Can't get above picture to look right, going to take a picture of it and save it in the post

A and B show the start position and Ball A and Ball B shows where they finish

Homework Equations


M1V1 + M2V2 = M1V1'+ M2V2'
Using inverse trig?

The Attempt at a Solution


I saw basically the same problem in Khan's academy and in there he had one of the two ball's final velocity given. I have no real idea how to solve for two variables but here was my try:
Momentum in X initial= 5.5 * .03 = .165
Momentum in Y initial= 0
m1v1+ m2v2= m1v1'+ m2v2'
.030*5.5 + 0 = .03v1' +.055v2'
 

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You should have three equations,

Energy before = energy after

Momentum in x direction before = momentum in x direction after

Momentum in y direction before = momentum in y direction after
 
Ok, well the energy before and after equation is:
(.03*5.5)+ (0.055*0)= (.03*V1')+(.055*V2')
Momentum in X before:
.030*5.5
Momentum in the Y before:
0
Momentum final for X must equal .165
Momentum final for Y must equal 0
I do not really understand how I can use this to find two velocities without knowing atleast one of them. How do I use the angles given to help me figure this out?
 
Write it out, if you see it written out it might click, if not it did not take too much time. I don't think you need the energy equation. You have two unknowns, the magnitudes of the velocity of each mass after collision so you only need two equations in the unknowns.
 

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