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Moderator is used in a nuclear to slow d...

Moderator is used in a nuclear to slow down fast neutrons generated after a fission event in the reactor consider a fast neutron (mass `m_(n)`) moving at speed v. The neutron hits a moderator nucleus (Mass M), which is originally static, and gets scattered elastically by `180^(@)`
(a) Find te rato of kinetic energy of the neutron after and before collision.
(b) Show that when `Mgtgtm_(n)`, neutron does not lose much energy and therefore, a moderator should have a small mass number.

Text Solution

Verified by Experts

The correct Answer is:
`((M-m_(n))/(M+m_(n)))^(2)`
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Knowledge Check

  • Substance used to slow down the fast neutrons released during nuclear fission is called?

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    Fuel
    B
    Moderator
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    Reflecting rods
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    A
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    2.If both assertion and reson are true but reason is not the correct explanation of assertion.
    C
    3.if assertion is true but reason is false.
    D
    4. If both assertion and reason are false.
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