Problem

The electric field in a region is given by

\mathbf{E} = \frac{E_0 x}{l} \hat{i}

. Find the charge contained inside a cubical volume bounded by the surfaces

x = 0

x = a

y = 0

y = a

z = 0

and

z = a

. Take

E_0 = 5 \times 10^3 \text{ N/C}

l = 2 \text{ cm}

and

a = 1 \text{ cm}