OnlineCBT
Physics · WORK, ENERGY AND POWER
हिन्दीIn an elastic head-on collision between two bodies of masses \( m_1 \) and \( m_2 \) (\( m_2 \) initially at rest), the ratio of the final speed of \( m_1 \) to the final speed of \( m_2 \) is \( 1 : 4 \). If \( m_1 \) continues in its original direction of motion, then the ratio \( m_1 / m_2 \) is:
Correct answer · Option 3
\( 2 \)
Explanation
We have \( \frac{v_{1f}}{v_{2f}} = \frac{(m_1 - m_2)/(m_1 + m_2)}{2m_1/(m_1 + m_2)} = \frac{m_1 - m_2}{2m_1} \). Given this ratio is \( 1/4 \), we get \( \frac{m_1 - m_2}{2m_1} = \frac{1}{4} \implies 2(m_1 - m_2) = m_1 \implies 2m_1 - 2m_2 = m_1 \implies m_1 = 2m_2 \implies m_1/m_2 = 2 \). Hence, Option 3 is correct.
