Q 12-01-062JEE MainJEE Main 2024 (9 Apr, Shift 2)Medium
An electric field $\vec E = (2x\hat i)\ \text{N C}^{-1}$ exists in space. A cube of side $2\ \text{m}$ is placed in the space as shown in the figure. The electric flux through the cube is ______ $\text{N m}^2/\text{C}$.
Numerical value type. Enter your answer.
Answer: 16
The field is along $x$, so only the two faces perpendicular to $x$ contribute. They are at $x = 2\ \text{m}$ and $x = 4\ \text{m}$, each of area $4\ \text{m}^2$:
$$\Phi = \left[E(4) - E(2)\right]A = (8 - 4)\times4 = 16\ \text{N m}^2/\text{C}$$
Solution by Sreeraj P, M.Sc Physics