The Original Reactor Built in 1942 Was Just "Barely" Critical

question 42

Multiple Choice

The original reactor built in 1942 was just "barely" critical because the natural uranium that was used contained less than 1% of the fissionable isotope U-235 (half life 713 million years) .What if,in 1942,the Earth had been 9 billion years old instead of 4.5 billion years old? Would this reactor have reached critical stage with natural uranium? Why?

• A)No.The age of the Earth has nothing to do with the reactor reaching critical stage with U-235.
• B)No.1% of the fissionable isotope U-235 is insufficient for the reactor to reach critical stage no matter what the age of the Earth.
• C)Yes.If the Earth had been twice as old there would have then been twice as much fissionable U-235 present and the reactor would have reached critical stage.
• D)No.The increased age of the Earth would mean that there would be a much smaller percentage of U-235,thus not enough for the reactor to reach critical stage.

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Definitions:

Supply Curve

A graphical representation showing the relationship between the price of a good and the amount of it that producers are willing to supply at each price level.

Total Variable Costs

The sum of all costs that vary directly with the level of production or output in the short term.

Output

The quantity of goods or services produced within a given time frame by a firm, sector, or country.

Equilibrium Price

The market value at which there's a perfect match between quantity of goods available and quantity desired by buyers.