2D Conservation of Momentum Question

In summary: What are the formulas to solve it?In summary, the collision between the steel ball of mass and velocity 2.0 m/s [E] and the 1.2 kg copper ball initially moving 1.0m/s [W] resulted in a glancing collision, causing the steel ball to have a velocity of 1.5 m/s [W 30 degrees N] and the copper ball to move in the direction [E 47 degrees S]. The question of whether the collision is elastic or not is dependent on whether there are any losses in the collision, which would affect the total momentum and energy before and after the collision. To solve this problem, it is helpful to draw diagrams, label known values, and set up
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A steel ball of mass moving with a velocity of 2.0 m/s [E], strikes a 1.2 kg copper ball initially moving 1.0m/s [W]. The collision is a glancing one, causing the steel ball to have a velocity of 1.5 m/s [W 30 degrees N] and the copper to move in the direction [E 47 degrees S]. Is the collision elastic?

There seems to be so many unknowns in this question, which is why I seemingly can't combine any formulas. How should I attempt to solve this?
 
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To do conservation questions, there is a discipline to keep track of what you know and what you don't.

Start out with "before" - and draw a diagram for the situation.
Drawing diagrams is very good even if the final answer does not require them - they are a computational tool.

Label the diagram with what you know - like the masses and the speeds.
Break any vectors into components - in this case you have E and N components (think of N as the y-axis if it helps).
Any values you don't know, just leave as letters. For eg, you don't know the mass of the east-bound mass - just leave it as m and move on.
What to do about it will become clear later.

Next to the diagram, write out the total momentum in the picture, as two components, and write out the total energy (it's just a magnitude).

Next start a new diagram called "after"
do the same thing - diagram, components, final momentum (vector) and energy.

next you write:
energy: before=after ... check this by doing the math.
momentum: before = after ... check again

of course this is the situation if there are no losses - in which case these are 3 simultanious equations and two unknowns.
if there are losses, there will be no solution that satisfies all three equations.

Does it pan out? Is there a simultanious solution?
 
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1. What is the conservation of momentum in 2D?

The conservation of momentum in 2D is a fundamental law of physics that states that the total momentum of a system remains constant in the absence of external forces. This means that in a closed system, the combined momentum of all objects in the system will stay the same before and after a collision or interaction.

2. How is momentum conserved in 2D collisions?

In 2D collisions, the total momentum of the system is conserved in both the x and y directions. This means that the sum of the momenta in the x-direction before the collision is equal to the sum of the momenta in the x-direction after the collision, and the same applies for the y-direction.

3. What are the equations for calculating momentum in 2D?

The equations for calculating momentum in 2D are px = mxvx and py = myvy, where px and py are the momenta in the x and y directions respectively, mx and my are the masses of the objects, and vx and vy are their velocities in the x and y directions.

4. How does the conservation of momentum apply to real-life situations?

The conservation of momentum applies to real-life situations such as collisions between vehicles, objects falling from a height, or even two people pushing against each other. In each of these scenarios, the total momentum of the system remains constant, even if individual objects experience changes in momentum.

5. What are some examples of 2D collisions?

Some examples of 2D collisions include a car crashing into a wall, a pool ball colliding with another pool ball, or a bullet hitting a target. In each of these collisions, the total momentum of the system is conserved in both the x and y directions.

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