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Physics · WORK, ENERGY AND POWER
हिन्दीIn a nuclear reactor, heavy water (\( \text{D}_2\text{O} \)) is preferred over ordinary water as a moderator because deuterons have a mass close to that of a neutron. In a head-on elastic collision of a neutron with a stationary deuteron (\( m_d \approx 2 m_n \)), the percentage of the neutron's initial kinetic energy transferred to the deuteron is approximately:
Correct answer · Option 1
\( 88.9\% \)
Explanation
Fraction transferred is \( f_2 = \frac{4m_1 m_2}{(m_1 + m_2)^2} = \frac{4(1)(2)}{(1+2)^2} = \frac{8}{9} \approx 88.9\% \).
