Answer:The first task of a nuclear weapon design is to rapidly assemble a supercritical mass of fissile uranium or plutonium. A supercritical mass is one in which the percentage of fission-produced neutrons captured by another fissile nucleus is large enough that each fission event, on average, causes more than one additional fission event. Once the critical mass is assembled, at maximum density, a burst of neutrons is supplied to start as many chain reactions as possible. Early weapons used a modulated neutron generator codenamed "Urchin" inside the pit containing polonium-210 and beryllium separated by a thin barrier. Implosion of the pit crushed the neutron generator, mixing the two metals, thereby allowing alpha particles from the polonium to interact with beryllium to produce free neutrons. In modern weapons, the neutron generator is a high-voltage vacuum tube containing a particle accelerator which bombards a deuterium/tritium-metal hydride target with deuterium and tritium ions. The resulting small-scale fusion produces neutrons at a protected location outside the physics package, from which they penetrate the pit. This method allows better control of the timing of chain reaction initiation.
Explanation:
Maybe this example could help you to understand this problem.
https://image.slidesharecdn.com/121howmanyatoms-091201144624-phpapp02/95/12-1-how-many-atoms-17-728....
The correct answer among the choices given is option A. Eustachian, Pharynx, Bronchi are structures that ensembles a tube. The Eustachian tube is a narrow passage from the pharynx to the middle ear. Pharynx is a passageway leading from the oral and nasal cavities to the larynx and the esophagus. Lastly, bronchi is an airway in the respiratory tract.
Answer:
Mass
Step-by-step explanation:
Usually, you plot the independent variable along the horizontal (x) axis and the dependent variable along the vertical (y) axis.
Marcia's teacher plotted the mass of the sample along the x-axis and volume along the y-axis.
The mass is the independent variable, because that is <em>what the teacher varied</em>.
The volume is the <em>dependent variable</em>, because it <em>depends</em> on the mass.
Sample number is <em>wrong</em>, because it is not a variable.
Substance is <em>wrong</em>, because all samples consist of the same substance.
Density is <em>wrong</em>, because it is constant. It is the slope of the graph.
Answer:
the same is what is this question like what did u exame
