PHYS$220$

Written Homework #$12$

Ansel Foxley

$2)$

Nuclear fusion, the energy source of the Sun, hydrogen bombs, and fusion reactors, occurs much

more readily when the average kinetic energy of the atoms is high$$that is$,$ at high temperatures.

Suppose the atoms in the core of the sun have an average kinetic energy of $3$ x $1016$ J$.$

a$.$ What is the approximate temperature of atoms in the core of the sun?

b$.$ Pressures at the core of the sun are something like $26$ x $1015$ Pa$.$ Assuming the core of the

sun behaves like a gas, and that it is at the temperature you calculated in a$,$ how many

moles of atoms are there in a cubic meter of space in the core of the sun?

c$.$ How many moles of atoms are in one cubic meter of the air in the room you are in$?$

Assume the pressure in Greeley is $0\mathrm{.}8$ atm and the temperature is $20$C $($about $68$F$).$