In a typical fission event a nucleus absorbs a thermal neutron and splits into and…

PHYSICS · Subjective · A Level · Physics · Nuclear physics · Nuclear physics

Problem

In a typical fission event a

^{235}_{\;92}\text{U}

nucleus absorbs a thermal neutron and splits into

^{141}_{\;56}\text{Ba}

and

^{92}_{36}\text{Kr}

along with three neutrons:

^{235}_{\;92}\text{U}+n\;\longrightarrow\;^{141}_{\;56}\text{Ba}+^{92}_{36}\text{Kr}+3n.

The relevant atomic masses are:

^{235}_{\;92}\text{U}=235.04393\,\text{u}

^{141}_{\;56}\text{Ba}=140.91440\,\text{u}

^{92}_{36}\text{Kr}=91.92620\,\text{u}

n=1.00866\,\text{u}

. (i) Calculate the energy released in a single fission of

^{235}

U according to the above reaction. (ii) A nuclear power station delivers an electrical output of

1000\,\text{MW}

and operates at an overall efficiency of

35\,\%

. Using your result from part (i), estimate: (1) the number of fissions occurring each second in the reactor core, (2) the mass of

^{235}

U that must undergo fission in one full day of operation.