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Basically, a block the mass 1 is traveling with velocity 1 towards the stationary spring system with mass 2. How much will the spring system compress?
I originally thought the answer was C. (highlight)
1/2mv^2=1/2Kx^2
(mv^2)/K=x^2
Then equation C
But NO!
The answer is D (highlight)
For the initial KE, they set the formula to accompany the second mass.
m1v1=(m1+m2)vf
vf=m1v1/(M1+m2)
1/2(m1+m2)v^2
1/2(m1+m2)(m1v1/(M1+m2))^2
1/2(m1v1)^2
1/2(m1v1)^2=1/2Kx^2
Then derive equation D.
Why was is it not my first choice?
I have no idea why they decided to incorporate m2 into the KE equation. The mass 1 is the only mass with initial velocity, and 1/2m1v^2 IS THE COMPLETE ENERGY being applied in the system. It does not need mass 2.
I have no idea why they decided to solve it the way they did.
Basically, a block the mass 1 is traveling with velocity 1 towards the stationary spring system with mass 2. How much will the spring system compress?
I originally thought the answer was C. (highlight)
1/2mv^2=1/2Kx^2
(mv^2)/K=x^2
Then equation C
But NO!
The answer is D (highlight)
For the initial KE, they set the formula to accompany the second mass.
m1v1=(m1+m2)vf
vf=m1v1/(M1+m2)
1/2(m1+m2)v^2
1/2(m1+m2)(m1v1/(M1+m2))^2
1/2(m1v1)^2
1/2(m1v1)^2=1/2Kx^2
Then derive equation D.
Why was is it not my first choice?
I have no idea why they decided to incorporate m2 into the KE equation. The mass 1 is the only mass with initial velocity, and 1/2m1v^2 IS THE COMPLETE ENERGY being applied in the system. It does not need mass 2.
I have no idea why they decided to solve it the way they did.