A cubical volume is bounded by the surfaces \( x = 0 \), \( x = a \), \( y = 0 \), \( y = a \), \( z = 0 \), \( z = a \). The electric field in the region is given by \( \vec{E} = E_{0}x\,\hat{i} \). Where \( E_{0} = 4 \times 10^{4} \,\text{N C}^{-1}\text{m}^{-1} \). If \( a = 2 \,\text{cm} \), the charge contained in the cubical volume is \( Q \times 10^{-14} \,\text{C} \). The value of \( Q \) is _______.
