(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

2. Relevant equations

m1v1i + m2v2i = m1v1f + m2v2f (Conservation of momentum)

(1/2)m2*(v2i)^2 + (1/2)m1*(v1i)^2 = (1/2)m2*(v2f)^2 + (1/2)m1*(v1f)^2 (Conservation of energy)

3. The attempt at a solution

I separated the momentum into x and y components and got 2 equations

I used the conservation of energy (can be used since its elastic) and got another equation

-I have 3 unknowns and three equations...which gives me hope that this is solvable lol

1. The problem statement, all variables and given/known data

Here are my equations:

Momentum for x:

0 = m2*v2f*sin(theta) + m1*v1f*sin(75)

unknowns here: theta, v2f, v1f

Momentum for y:

m2*v2i = m2*v2f*cos(theta) + m1*v1f*cos(75)

unknowns here: theta, v2f, v1f

Conservation of energy equation:

(1/2)m2*(v2i)^2 = (1/2)m2*(v2f)^2 + (1/2)m1*(v1f)^2

unknowns here: v2f, v1f

Can you guys see if these equations are right before I start using the tedious algebra involved in this.

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# Homework Help: Conservation of momentum and energy problem (Please check if my setup is right)

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