<span>The motion of the medium is parallel to a longitudinal wave
and perpendicular to a transverse wave.</span>
![v'_2 = \frac{2m_1}{m_1+m_2} (4.3) - \frac{m_1-m_2}{m_1+m_2} (4.3)\\\\v'_1 = \frac{m_1-m_2}{m_1+m_2} (4.3) + \frac{2m_2}{m_1+m_2} (4.3)](https://tex.z-dn.net/?f=v%27_2%20%3D%20%5Cfrac%7B2m_1%7D%7Bm_1%2Bm_2%7D%20%284.3%29%20-%20%5Cfrac%7Bm_1-m_2%7D%7Bm_1%2Bm_2%7D%20%284.3%29%5C%5C%5C%5Cv%27_1%20%3D%20%5Cfrac%7Bm_1-m_2%7D%7Bm_1%2Bm_2%7D%20%284.3%29%20%2B%20%5Cfrac%7B2m_2%7D%7Bm_1%2Bm_2%7D%20%284.3%29)
<u>Explanation:</u>
Velocity of B₁ = 4.3m/s
Velocity of B₂ = -4.3m/s
For perfectly elastic collision:, momentum is conserved
![m_1v_1 + m_2v_2 = m_1v'_1 + m_2v'_2](https://tex.z-dn.net/?f=m_1v_1%20%2B%20m_2v_2%20%3D%20m_1v%27_1%20%2B%20m_2v%27_2)
where,
m₁ = mass of Ball 1
m₂ = mass of Ball 2
v₁ = initial velocity of Ball 1
v₂ = initial velocity of ball 2
v'₁ = final velocity of ball 1
v'₂ = final velocity of ball 2
The final velocity of the balls after head on elastic collision would be
![v'_2 = \frac{2m_1}{m_1+m_2} v_1 - \frac{m_1-m_2}{m_1+m_2} v_2\\\\v'_1 = \frac{m_1-m_2}{m_1+m_2} v_1 + \frac{2m_2}{m_1+m_2} v_2](https://tex.z-dn.net/?f=v%27_2%20%3D%20%5Cfrac%7B2m_1%7D%7Bm_1%2Bm_2%7D%20v_1%20-%20%5Cfrac%7Bm_1-m_2%7D%7Bm_1%2Bm_2%7D%20v_2%5C%5C%5C%5Cv%27_1%20%3D%20%5Cfrac%7Bm_1-m_2%7D%7Bm_1%2Bm_2%7D%20v_1%20%2B%20%5Cfrac%7B2m_2%7D%7Bm_1%2Bm_2%7D%20v_2)
Substituting the velocities in the equation
![v'_2 = \frac{2m_1}{m_1+m_2} (4.3) - \frac{m_1-m_2}{m_1+m_2} (4.3)\\\\v'_1 = \frac{m_1-m_2}{m_1+m_2} (4.3) + \frac{2m_2}{m_1+m_2} (4.3)](https://tex.z-dn.net/?f=v%27_2%20%3D%20%5Cfrac%7B2m_1%7D%7Bm_1%2Bm_2%7D%20%284.3%29%20-%20%5Cfrac%7Bm_1-m_2%7D%7Bm_1%2Bm_2%7D%20%284.3%29%5C%5C%5C%5Cv%27_1%20%3D%20%5Cfrac%7Bm_1-m_2%7D%7Bm_1%2Bm_2%7D%20%284.3%29%20%2B%20%5Cfrac%7B2m_2%7D%7Bm_1%2Bm_2%7D%20%284.3%29)
If the masses of the ball is known then substitute the value in the above equation to get the final velocity of the ball.
Build up of pressure between tectonic plates .
False:Laws are theories that have not been proven false.