What is the Ratio of Speeds After a Noncentral Elastic Collision?

AI Thread Summary
In a noncentral elastic collision between two spheres, one with a mass of 0.3 kg and the other 0.35 kg, the first sphere transfers 79% of its kinetic energy. The initial velocity of the first sphere (u1) is unknown, while the second sphere (u2) starts at rest. The calculations show that the ratio of their speeds after the collision is v1 : v2 = 1 : 3.224. The discussion emphasizes the importance of incorporating kinetic energy relationships into the calculations for accuracy. Ultimately, the correct application of kinetic formulas leads to a valid solution.
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Homework Statement



First sphere m=0.3 kg collide noncentraly and elasticaly with other sphere of m= 0.35 kg and transfer 79% of first sphere kinetic energy during that collision... u1 is not defined, u2 = 0 m/s

Ratio between speed after collision v1 : v2 = ??


Homework Equations



m1u1 + m2u2 = m1v1 + m2v2


The Attempt at a Solution



Tryied to make Ek = Ek1 + Ek2

m1u1 = m1v1 + m2v2

m2v2 = 0.79 m1u1
v2 = 0.677 u1

m1v1 = 0.21 m1u1

v1= 0.21 u1

so ratio would be

v1 : v2 = 0.21u1 : 0.677u1

so in conclusion

v1 : v2 = 1 : 3.224



But I don't know if it's false or right...
 
Last edited:
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hmmm , your solution doesn't seem logical enough to me .. for example why didnt you use the fact that k=0.mv^2 (or p^2/2m) ??notice what is the relationship between the kinetic energy and the velocity(or momentum) .. how would that change your calculations? .. please try again ..
 
Yeah... I got right solution after applying it with kinetic formula...

Thx nevertheless :)
 
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