Question

The energy liberated on complete fission of `1 kg` of `._92 U^235` is (Assume `200 MeV` energy is liberated on fission of `1` nucleus).
A. `8.2 xx 10^10 J`
B. `8.2 xx 10^9 J`
C. `8.2 xx 10^13 J`
D. `8.2 xx 10^16 J`

Answer 1

Correct Answer - C
( c) Mass of a uranium nucleus
=`92 xx 1.6725 xx 10^-17 + 147 xx 1.6747 xx 10^-27`
=`393.35 xx 10^-27 kg`
Number of nuclei in the given mass
=`(1)/(393.35 xx 10^-17) = 2.542 xx 10^24`
Energy released `= 200 xx 2.542 xx 10^24 MeV`
=`5.08 xx 10^26 MeV = 8.135 xx 10^13 J ~~ 8.2 xx 10^13 J`.