What element was used as fuel for the "Fat Man" bomb?

What element was used as fuel for the "Fat Man" bomb?

• A. Uranium-235
• B. Plutonium
• C. Thorium
• D. Neptunium

Answer: (B)

The main idea is identifying which fissile material powered Fat Man. Fat Man used plutonium-239 as its fuel. The bomb was an implosion device, with a plutonium core that was symmetrically compressed by explosive lenses to reach a supercritical state and start the chain reaction. Plutonium-239 was chosen because it can be produced in reactors and formed into a compact, uniform pit ideal for this implosion design. Uranium-235, by contrast, was used in the other bomb with a different gun-type mechanism, while thorium and neptunium were not used as the primary fissile fuel for Fat Man.

The main idea is identifying which fissile material powered Fat Man. Fat Man used plutonium-239 as its fuel. The bomb was an implosion device, with a plutonium core that was symmetrically compressed by explosive lenses to reach a supercritical state and start the chain reaction. Plutonium-239 was chosen because it can be produced in reactors and formed into a compact, uniform pit ideal for this implosion design. Uranium-235, by contrast, was used in the other bomb with a different gun-type mechanism, while thorium and neptunium were not used as the primary fissile fuel for Fat Man.