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(UNICAMP - 2020 - 1 fase)Nuclear fusion is a react

Física | física moderna | noções de teoria da relatividade | equivalência entre massa e energia
UNICAMP 2020UNICAMP InglêsTurma ENEM Kuadro

(UNICAMP - 2020 - 1ª fase) 

Nuclear fusion is a reaction in which atomic nuclei merge to form the nucleus of a new atom. The mass of the new atom’s nucleus is lower than the sum of the merging nuclei’s masses, a difference that is released as energy. This is, for instance, the reaction that occurs in the Sun. The energy released during fusion can be calculated by the equation \(E =\Delta mc^{2}\),  where \(\Delta m\) is the difference between the initial and final masses in the reaction, and \(c\) is the speed of light. When calculating the aforementioned energy, nucleus mass can be conveniently quantified using the atomic mass unit (u), which is roughly equivalent to 900 MeV (1 u \(\rightarrow\)  900 MeV). Consider the hypothetical nuclear fusion reaction \(_{}^{222}\textrm{X}+\, _{}^{4}\textrm{Y}\rightarrow\, _{}^{221}\textrm{Z}\).  Note that the masses of \(_{}^{222}\textrm{X}\) , \(_{}^{4}\textrm{Y}\)and  \(_{}^{221}\textrm{Z}\) are 222u, 4u, and 221u, respectively.

The amount of energy released in this reaction is 

A

5 MeV.

B

450 MeV.

C

900 MeV.

D

4500 MeV.