According to Sabine's formula, the reverberation time $T$ of a room is given by: $T = \frac{kV}{S}$ where $V$ is the volume of the room, $S$ is the total surface area (representing total absorption), and $k$ is a constant. When all dimensions (length, breadth, and height) are doubled: New volume, $V' = (2L) \times (2B) \times (2H) = 8V$ New surface area, $S' = 2(2L \times 2B + 2B \times 2H + 2H \times 2L) = 4S$ New reverberation time, $T' = \frac{kV'}{S'} = \frac{k(8V)}{4S} = 2 \left(\frac{kV}{S}\right) = 2T$ Given the initial reverberation time $T = 1 \text{ second}$, the new reverberation time is: $T' = 2 \times 1 = 2 \text{ seconds}$