Question

A uniform electric field is given as \(\vec{E}=4\times 10^{4}\hat{j}\ \text{N/C}\). The flux of this field through a square of side \(10\ \text{cm}\) whose plane is parallel to the Y-Z plane is

• A. \(400\ Vm\)
• B. \(200\ Vm\)
• C. zero
• D. \(1600\ Vm\)

Hint:

Flux is the dot product of field and area vector. The area vector of a square in the YZ plane points along the X-axis.

Answer 1

The Correct Option is C

Step 1: Geometry
The field is along the Y-axis, and the square lies in a plane that contains the Y-axis. The field runs parallel to the surface.

Step 2: No lines cross
No field lines pass through the surface, so the flux is zero.

Step 3: Result
The area $0.01\ \text{m}^{2}$ does not matter here. Option (C) is correct.

Final Answer:
The flux through the square is zero. \[ \boxed{\text{(C) }\text{zero}} \]