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Physics · WORK, ENERGY AND POWER
हिन्दीA ball of mass \( m_1 \) collides elastically and head-on with a stationary ball of mass \( m_2 \). If the first ball recoils with one-third of its initial speed, the ratio \( m_1 : m_2 \) is:
Correct answer · Option 4
\( 1 : 2 \)
Explanation
Since it recoils, \( v_{1f} = -\frac{1}{3}v_{1i} \). From the elastic collision formula: \( v_{1f} = \frac{m_1 - m_2}{m_1 + m_2}v_{1i} \implies \frac{m_1 - m_2}{m_1 + m_2} = -\frac{1}{3} \implies 3m_1 - 3m_2 = -m_1 - m_2 \implies 4m_1 = 2m_2 \implies \frac{m_1}{m_2} = \frac{1}{2} \).
