- #1
flyingpig
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Breaking rules of Algebra?
I am copying this problem from my textbook. It is about momentum and Kinetic energy
My problem lies in part B. According to Part A, v₁'=v₁‐kv₂'
But in part B, (v₁‐kv₂')²+kv₂'²=v₁'², see the problem? v₁‐kv₂' has been plugged into v₁'² and it reappeared again on the right hand side.
Right I need help. KEEP IN MIND THAT "K" IS THE RATIO OF M2/M1
ALSO[/SIZE] PLEASE SHOW ME HOW TO GET TO PART C
Homework Statement
I am copying this problem from my textbook. It is about momentum and Kinetic energy
By rearranging the top equation, we have PART A
v₁'=v₁‐kv₂'
v₁'²+kv₂'²=v₁²
Now we can substitute the top equation into the bottom: PART B
(v₁‐kv₂')²+kv₂'²=v₁'²
v₁²‐2kv₁v₂'+k²v₂'²+kv₂'²=v₁'²
After the cancellations, we are left with PART C
‐2v₁+kv₂'+v₂'=0
The Attempt at a Solution
My problem lies in part B. According to Part A, v₁'=v₁‐kv₂'
But in part B, (v₁‐kv₂')²+kv₂'²=v₁'², see the problem? v₁‐kv₂' has been plugged into v₁'² and it reappeared again on the right hand side.
Right I need help. KEEP IN MIND THAT "K" IS THE RATIO OF M2/M1
ALSO[/SIZE] PLEASE SHOW ME HOW TO GET TO PART C
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