Physics · JEE | WORK, ENERGY AND POWER

In a two-dimensional elastic collision between two masses \( m_1 \) and \( m_2 \) with initial velocity \( v_{1i} \) along the x-axis, what is the equation representing the conservation of momentum along the y-axis (where \( \theta_1 \) and \( \theta_2 \) are the scattering angles)?

1. A
   \( m_1 v_{1i} = m_1 v_{1f} \cos\theta_1 + m_2 v_{2f} \cos\theta_2 \)
2. B
   \( m_1 v_{1i} \sin\theta_1 = m_2 v_{2f} \sin\theta_2 \)
3. C
   \( 0 = m_1 v_{1f} \sin\theta_1 - m_2 v_{2f} \sin\theta_2 \)
4. D
   \( m_1 v_{1f} \sin\theta_1 + m_2 v_{2f} \sin\theta_2 = m_1 v_{1i} \)