Question #83c7e

1 Answer
Oct 14, 2015

I found that depends on the ratio of the two masses only.

Explanation:

I tried considerng Conservation of Momentum pp (along xx):
Before: 00
After: m_1v_1+m_2v_2m1v1+m2v2
and together:
0=m_1v_1+m_2v_20=m1v1+m2v2

so: m_1v_1=-m_2v_2m1v1=m2v2

squaring both and rearranging:

v_1^2/v_2^2=m_2^2/m_1^2v21v22=m22m21

Kinetic Energy is K=1/2mv^2K=12mv2
So:
K_1/K_2=(cancel(1/2)m_1v_1^2)/(cancel(1/2)m_2v_2^2),
substituting: v_1^2/v_2^2=m_2^2/m_1^2
K_1/K_2=(cancel(m_1))/(cancel(m_2))*m_2^cancel(2)/m_1^cancel(2)=m_2/m_1