Which physical quantity in a nuclear reaction is considered equivalent to the Qvalue of the reaction?

Explanation

To determine which physical quantity in a nuclear reaction is considered equivalent to the Q value of the reaction, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Q Value**: The Q value of a nuclear reaction is defined as the difference in the total energy of the products and the total energy of the reactants. It is a measure of the energy released or absorbed during the reaction.

2. **Mass-Energy Equivalence**: According to Einstein's mass-energy equivalence principle, energy can be converted into mass and vice versa. The relationship is given by the famous equation \(E = mc^2\).

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