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A nucleus of uranium decays at rest into...

A nucleus of uranium decays at rest into nuclei of thorium and helium. Then,

A

the helium nucleus has less kinetic energy than the thorium nucleus

B

the helium nucleus has more kinetic energy than the thorium nucleus

C

the helium nucleus has less momentum thanthe thorium nucleus

D

the helium nucleus has more momentum than the thorium nucleus.

Text Solution

Verified by Experts

The correct Answer is:
B
`._(92)U^(238) to ._(90)Th^(234)+._(2)He^(4)`
Momentum conservation
`implies| vecp_(Th)|=|vecp_(He)|=p`
Kinetic energy `K=(p^(2))/(2m)`
`Kprop(1)/(m)`
`m_(He) lt m_(Th)`
`impliesK_(He) gt K_(Th)`
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