Question

which energy transformation occurs in the core of a nuclear reactor?
nuclear energy → mechanical energy
nuclear energy → thermal energy
thermal energy → nuclear energy
mechanical energy → nuclear energy

Explanation:

In a nuclear reactor's core, nuclear fission (a nuclear process) releases energy. This energy is in the form of heat (thermal energy). So the energy transformation is nuclear energy (from fission) converting to thermal energy. The other options are incorrect: nuclear to mechanical is not direct in the core, and the reverse transformations (thermal to nuclear, mechanical to nuclear) don't happen in the reactor core as nuclear reactions are the source, not the result of thermal/mechanical energy.

Answer:

B. nuclear energy $
ightarrow$ thermal energy (assuming the second option is labeled B; if the original options had labels like A, B, C, D, adjust the label as per the original. Since the user's image shows the second option as "nuclear energy $
ightarrow$ thermal energy", the correct answer is that option.)