What shape uses the smallest amount of material when creating a critical mass?
The smallest amount of a fissionable material that will give a self-sustaining chain reactions is called the?
What is the amount of fissionable material that must be present in order for a nuclear reaction to take place called?
The words fissile and fissionable are not generally taken to mean the same thing. Fissile materials can sustain a chain reaction with low energy neutrons. Fissionable materials can sustain a chain reaction, but only if the energy of the neutrons present is sufficiently high. Critical mass is the amount of material needed, in ideal circumstances, to start a chain reaction without neutrons other than those produced internally. 235U is fissile, and has a critical mass…